period question??? plz help me?

Ok so I am turning 14 in a week and a half and I got my period June of 2015 ( it's February 2016 now) Anyway my very first period was heavy and lasted 9 days and I was told that was normal. The next following months my periods were very very light like barely anything on the pad and lasted 2-4 days. After this , I got another very light period lasting about 3 days. But Then about 2 WEEKS after that I had a very heavy period lasting 5 days. That was one month ago. Now... My period started last Thursday( it's about to be Wednesday) and was very heavy. I would soak a pad every 2 hours and 30 minutes. When I stand at school I feel it GUSH OUT( sorry tmi:( ) SOOO what I'm saying is I've had my period for 7 days and it's been heavy bleeding all the days!!! I normally have light and short periods but all of a sudden it's very heavy and lasting a week and still going. What's wrong. Am I losing too much blood now. Should I go to the doc. Even though I hate it. Guys u don't know how much I want u to answer I'm so scared ;(