Yup.. I have waaaaay too many hang nails because of that

I sometimes find the bare floor more comfortable than the couch and will fall asleep, sprawled out in the middle of my living room. (dunno if it's a bad habit, might just be weird..)

Not weird at all, I know a few people who prefer that.

I sometimes have the odd habit of biting my fingers for no particular reason. I still don't remember when it first started or why I do it

I don't bite my fingers but I do bite my fingernails .
I sometimes have a bad habit of eating really late like at 10pm or later

IC my character has a bad habit of getting very angry very quickly and that makes her accidental magic go off

Pfft, Juni has a habit of getting too angry and physically attacking people. I think your character is good lmao

I have a bad habit of going on HIO and leaving homework to last second

I don’t.
I can get impatient very quickly. In, like, two minutes.

That doesn't happen with me.
A bad habit of mine is if I intend to go to bed earlier, I end up staying awake even later than usual.

No I don’t do that but I kinda get why

A bad habit of mine is that 4 or 5 nights a week I put my hair up in a tight, high ponytail. (This is for Taekwondo.. you have to have your hair pulled up if it is to your shoulders ) And leave it in all night and maybe most of the next day. It gives me a horrible headache and still, I forget to take it out!

No I do not do that.

I have a terrible habit of playing with my hair. People mistake it for me being flirty or whatever but in reality it's just a nervous habit.

I do that, usually when thinking or nerves!

Randomly pressing a bruise to see the discoloration of it fade and reappear for fun.