Its perfectly ok if you don't want a GF at this time. Right now you are going to be a JR. and trying to figure out what you want in life for wither college, jobs, or whatever.
I am not telling you not to date because it is ok but do it when you are ready to. If you don't want to go through those hardships at a young age then don't.
If people don't understand why you don't go out with girls and they tease you then just leave them alone. Its your life and choice not theirs.