I can understand that you have considerably advanced in Krishna Consciousness because your heart is simple. Girls and women are generally very soft hearted and they take things very easily, but then there is also chance of being misled. So you chant the Holy Name of Krishna and Krishna will keep you from being misled.
Last night there was initiation ceremony in which your beads were sanctified. You'll take on string of small beads for sticking on your neck and the bigger ones you can chant according to the rules.
There are 10 kinds of offenses in chanting Hare Krishna and everyone should avoid such offenses. They are listed on the paper and you can have it from Brahmananda. Krishna Consciousness is very nice, simple, and sublime. If you stick to this principle, undoubtedly you'll be happy both in this life and next life.
For the present you should continue going to school because education is important. Without education nobody has any social position and all our students in Krishna Consciousness are expected to be preachers. So preachers must have sufficient education because they have to meet with so many opposing elements. Education should be continued at the same time chanting should be continued. There will be no difficulty.
I am very glad to learn you are chanting 48 rounds. Actually it is all right that one should chant 64 rounds, even 16 rounds, so if one is able to chant more than 16 rounds up to 64, it is very good.
You fix up your rounds. Try to increase it but never decrease it.