Miscariage?? Im Scareddd

Ive been on birth control for 5 months. I started having 2 periods a month once in the middle of my regular pills, and another when I started my period pills. I kept taking them thinking it would get back on the right track.
My periods havnt been like red blood its been a brownish dark color. The last time I had sex I got this brown discharge after wards. The last time I had sex was about a month ago.
Then this month I started my period in the middle of my regular pills again (like always) only when I got to my period pills I didnt start my period at all!!
Is it possible I could be pregnant? Then after the 3rd period pill I started spotting I was about to get in the shower when I felt something coming out of me it was a clear like sack. I know it sounds weird but was that like a miscariage?
I still havnt started my period just like this nasty purple stuff for a while and now nothing. Im scared and confused whats going on.

Help me pleasssssee!!! :( :( :(