It is completely normal to be a few days late or a few days early.
Periods aren't perfect, you have different symptoms some months, some have more cramps then others, heavier bleeding, more soreness in chest, ect.

There is no reason to be worried at this point. This year I skipped an entire month! I don't know if it was because I was working out more/less often or what but I went about 65 days between periods. (I was never so happy to start having cramps and bleeding my whole life xD