Suggest Treatment For Periods Coming For 3 Weeks A Month?

I am on the Depo shot for birth control. I am trying to find a solution for my period always being on. It has been on for about 2 and a half weeks now after changing climate and visiting New York for a week. But I have been having a problem with my cycle for awhile now and it will not go off and stay off
. I also have sickle cell anemia and some days I feel extremely light head and very hormonal. This is also interfering with my sex life because every time me and my boyfriend decide to be intimate. My cycle has come on 2 times while we were in the middle of intimacy. Please help me to find a solution to
this problem because I shouldn't have a period 3 weeks out of a month. What would you recommend or suggest for me to do?
Sincerely,
Demetria