Lucky you, having no period pains! On the other hand, it can be useful to have at least some idea when to expect your period. I’d suggest you make a note in your diary every time you have a period and note how many days it lasts. That way, after a few periods, you might be able to see if any of your periods come at the same interval, and see a “pattern” that tells you when your next period will start. It might also be a good idea to make sure you always have a towel or two in your school bag.