@abpositive, I am happy that you think the things like you being pushed and tripped are just minor things 'cause that means you are a strong person. However, I am a bit worried that you would still ignore these when they escalate. Please know that it is never right to physically harm or be harmed by anyone.
When I was young I was treated in a similar way in high school. Not cause I was gay (I hadn't figured that out yet) but because I was a cheerleader. I was pushed into the lockers, threatened to be beaten up on my way home, etc. So, I know a little bit of how that feels. It causes an insecurity and a little bit of a fear of people.
Just know that you are a beautiful person and that the people who are messing with you are the ones with major character flaws. Is there an lgbt support group at your school? If so, that would be an excellent way to increase your support and keep you from feeling isolated. If there isn't one - maybe you can start one! A good way to take the power!
Hmmm, we should come up with a fun, harmless, silent prank that you can do for a laugh - nothing dangerous or violent - just silly hmmmmm - and done in a well thought out way so it is never traced back to you ..... What can I say, I have a devious side
On the serious side, you should tell someone - what are you parents and the school authorities like?
College should be much better! So many of them do have lgbt support groups. If not at your college perhaps in the surrounding community. Not only will they be supportive but also alot of fun! The lgbt community is a strong, supportive family to each other.
There are quite a few bi people about the same age as you on this site. You might try reading through the posts and finding some of them. You can have private conversationa even through pm.
Have you picked a major yet in College or experimenting around to see what interests you?
You may have heard this over and over and over, "it's not you, it's them". But it is sincerely true. I ask you this, if you don't like someone, do you immediately push them around? I bet you don't because you are polite, respectful, and decent. They aren't, that one I can bet my arm on.