What Causes Severe Cramps During Periods?

I'm a 19 yr old female and I just recently started my period maybe two days ago. My cramps used to be really severe but seemed to go down after a while. Well this time when I started my period the severe cramps came back and were HORRIBLE. Now I've been feeling sharp pains in my lower right area, as well as in my back, and sharp pains on my right side. My stomach is bloated and feels bubbly and weird (rumbling). My feet are also feeling tingly. I've never felt this way on my period. I was very scared it could be my appendix but I haven't got sick. Although about two years ago I felt as if I was dying..I laid in bed for 3 days straight; vomiting everyday and diarrhea and the smell of food made me sick, also I had a sharp pain in my lower right back the whole time. I finally went to the doctor, the doctor was scared it could have been my appendix but gave blood work and everything was fine. The doctor then said I pulled a muscle in my back? Throughout my life I've experienced painful feelings in my vagina area for no reason whatsoever AND a sharp feeling in my back comes and goes but the last few days it has lasted longer than ever! Also pain and bleeding during intercourse and I'm began to think something could be wrong, while everyone is telling me it's probably just a cyst on my ovary?....What could be wrong??