It sounds like you are starting your period ~ welcome to womanhood~ You can take tylenol
or midol for the cramps, you will need tampons/pads (if your cramps are really bad you may want to just wear a pad at first), you will continue to bleed for 3-5 days, and may notice some bloating
along with sore muscles and headaches
. If you have more questions you should talk to your mom, a close friend's mom, an older sister (yours or a friends), or your school nurse.
But to answer your question -- 100% normal. ^_^