I'm writing a Fanfic to tie up some loose ends in a book series I like, and this is so much harder than it was in middle/high school! Issues I'm having:

1. Focus (I always have this problem though)
2. Character names. 30 pages in I realized I had been spelling a character's name wrong the whole time OTL
3. Deadline. The authors have been hinting that they might release a secret 5th book of the series and I want to finish mine before they release theirs!
4. Whenever I start writing all I want to do is draw, and whenever I draw all I want to do is write!
5. Too many ideas. (other fanfics, potential plots changes, etc)
6. Anxiety.

Does anyone ever have these problems?

I hear ya on a lot of these things. I have beed trying to write an original story and I'm always distracted by something else. Like you said, I tend to want to play a video game or draw when I am trying to write. though one of my biggest issues is I almost ALWAYS get hit by writing inspiration whenever I am only about 20-30 min from having to leave to go somewhere (work, a friend's house, etc)

Then I tend to decide that whatever I've written isn't good enough and I rewrite it and get hung on ironing out more character details before I can do much writing at all.

Oh, I feel you! I always get the most writing inspiration as I'm falling asleep, and being an insomniac sleep is a precious commodity.

I found listening to CreepyPastas (or other stories being read) helps me write and helps me write better, as it helps me get more imaginative and helps with my flow.

Oh yeah? I might try that out. I sometimes starting getting little random inspirations when I'm laying down to sleep so I often have my computer next to me just in case I need to jot something down quickly. I generally listen to the multitudes of "epic" musics on Youtube, mostly the ones without words as they often give plentiful inspiration and set the right moods for the scenes I am /trying to write. (don't always work if I'm too distracted though. lul)

I also have trouble with anxiety too but I especially hate that feeling of self-flagellation when you miss something crucial because you hadn't realized it it was going to be important so soon; it drives me away from writing which makes more more anxious about getting back into it. Sometimes I get anxiety when hit Writer's Block but I have a strategy: on the top of every chapter, I put "Just Try" in parenthesis when I first start and delete that when I'm done.

I get distracted easily as well when writing or drawing, I found using the pomodoro method works wonders to keep me focused.

If you don't know what that is, it's basically when you work on something for 30 minutes and then take a break for 15-30 minutes. You can extend your time if you're on a roll, but don't stop before your time is up. 30 minutes might not but much but for me, at least knowing I did some of what I set out to do helps me feel so much better and motivates me further. ^^

You can split your times into different things or just work on one thing on and off for all your time blocks.

Another thing to add to it is to stick to one project at a time. I have your issue of too many ideas, a professional comic artist I follow suggests to stick to one project at a time. So, you should probably go with the thing most important to you currently. [this has also helped me, now I'm actually getting somewhere in my own story]

I have these problems. Like for real, my first fanfic did get 531 views, 61 votes, and 73 chapters and all but I totally bombed it. Now for the rest, I'm actually proud of the other fanfics I've written. I've written: 24 BTS fanfics, 1 rant book, 1 cover shop, 1 Big Bang fanfic, 1 Netflix fanfic, 13 are complete 11 are still being worked 2 other stories of the 11 are almost complete

I've got so many ideas when I start to write one another idea pops up, and then I get side tracked

Sometimes the anxiety is worse when you're writing in small fandoms and/or rarepairs. Like... some of the fic I'm currently plotting is for Xenogears, after the end of the game, and while I want to get the characters right... I also don't want to write some of the relationships. Not as they were in the game anyway. DX Elly unintentionally pressed Fei's trauma buttons in game (he'd been badly abused as a kid-toddler through oh, about 7) by his mother, and if she'd known she would've handled it differently, I think. But the trauma had been bad enough Fei kept repressing it every time he remembered, and they worked better apart. :/

Like... I think IF Elly was going to be all romantic with Fei it would be better in 10 or 15 years, after Fei got the therapy he needed. Her too, because her youth (while not as horrible as his) wasn't easy either.

I'm also nervous about the Legend of Dragoon fic I'm currently plotting... it's the sidequest where you can fight the bound original Dragoons in Vellweb? And each chapter would be a combination fight/flashback/"history lesson" about the original Dragoon Campaign, but I don't know if I can do it justice. The only three original Dragoons that had real screen time were Shirley, Zeig and Rose-but Shirley was like half an hour on the first disk and Zeig wasn't... himself, shall we say. I dunno if I can pull it off.

Aww man and Rose was the coolest too. I relate.

Mass Effect Fanfictions are like that too. The characters are so rich, doing them justice is so hard.

In order to get over my fears re: Legend of Dragoon, it's one of the fics I'm writing this November for Nanowrimo! I dunno if it'll be long enough to reach 50k words, so the other one is a Legend of Zelda: Majora's Mask fanfic.