What Causes Heavy Menstruation Along With Lower Abdominal And Vaginal Pain?

Hi, I ve been on the implant since August 2014 and had absolutely no problems within the first year and a half, my periods stopped and I had no pain, it was fantastic. However, on Christmas eve 2015 I started my period again, it was extremely heavy and painful, and I didn t come off my period until April this year. Since then my periods have been ridiculously heavy, and I ve now been on my period again since August. Along with the normal pain I get, I ve had severe lower right abdomen pain, stretching round to my back, and severe shooting pain inside my vagina. The pain hasn t stopped or dulled down in over a month and I find myself tired and run down all the time. I m really not sure whats happening but because I m only 18 I m quite scared of going to the doctor about it.