period pain - the pill?

Hi there, I am a 14 year old girl and I get extremely bad periods. They hurt like crazy and every morning I leak on my bed. I have missed school a lot because of my period.

The pain is in my lower abdomen and back. I have tried everything to make it better, eating bananas, heating packs, hot baths, yoga, exercise, different body positions, medication and none of it is working.

My flow is really heavy and my doctor told me to try some kind of medication to make my flow lighter but it didn't work and now he has suggested the pill. My parents are unsure of this and so am I. I am definitely not going to be engaging in sexual activity until I'm in a loving relationship and over 18(at least) so I don't need the pill for that and just because I would be taking it doesn't mean I will have sex. I really want to be able to skip a few periods instead of having 12 a year I could reduce it to 4 and time them as to when it won't affect my holidays, sports, important events, school exams, etc.

I have been reading online about the side effects and I'm concerned that I might gain weight. I enjoy modelling and cheerleading so I don't want to gain too much. Is this side effect true and if so, how much weight will I gain?

I had severe anaemia (iron deficiency) about 6 months ago, will this have any affect if I take the pill?

Last question, do you think I should take the pill?

Please leave warnings and benefits of the pill in your answer. Sorry for this post being so long, goodbye!