Forget safety issues. If you just got glasses and can "still see fine for the most part," your prescription is probably so light you will have no problems with glasses under your helmet. You would probably also have no problems with contact lenses except under extreme circumstances. As someone who wore glasses since second grade, had a contact prescription of -7.75 before lasik, and wore both through many different helmeted and non-helmeted activities, successfully and unsuccessfully, if you still have concerns or questions give me a call.