Is this cancer? Please help!

I’ve been on birth control for over a year and a half and I only ever get brown discharge before my period. I’m in the middle of my pack now and I had brown discharge yesterday. In the middle of the night I had a dream that I had sharp pains in my uterus, I’m not sure if the pain was real or not. Either way I had the brown discharge. Also for a long while now I will get like nerve pain in my upper left thigh sort of like a quick ache that comes and goes, it’s not constant . I know cervical cancer causes leg pain. Should I be concerned?