I take Mesygina and this month came a lot of flow, what to do?

Good afternoon, I'm 18, I take Mesygina to almost 1 year. I adapted very well. However, on January 15/01/12 I took it with 26 days due to appointments, but I always take 28 days on a regular basis. Day 01/31/2012 I have my normal mesntruation, always with little flow, it was to finish on Tuesday (07/02/2012), but from this date, the flow has increased a lot. Sunday 12/02/2012 is the next date to take. Detail: On Sunday, 05/02/2012 I had pain in the stomach, and I threw up. I took Plasil, probably something that makes me sick. I would like to know what is actually happening. Do I need to change? Which is the most advisable? Thank you!