Skipping Periods

I am 14 and just got my period last winter. I had it once in December for 4 days, skipped 4 months, then it came monthly, usually a couple days late and about 8 days long. I haven't had it  in September or October, and it always comes at the beginning of the month. I'm kinda worried and I honestly just want to stop worrying and have it come and get back to normal.