Cramps

Does anyone else get cramps so bad they throw up?? Only on the first day of my period, once on the first and second day. This has happened to me a total of about 5 times in the past year. Some cycles I will be fine, some I will just have bad cramps. About a year ago it happened for the first time, and I thought I threw up because I took medicine for cramps that morning on an empty stomach. But the next day I didn't take any medicine and I still threw up. I guess it's just from the pain? It happened 3 cycles in a row about a year ago, then once a few months ago, and today I started my period and it is happening again. I'm only 17 and my mom knows about it but said its probably just my hormones and irregular cycle. She refuses to put me on birth control to regulate my period because she thinks I'm too young and doesn't want me having sex (I have a boyfriend). I just want to know if it's anything to worry about and if anyone else has had the same problem.