brown spotting.

i haven't had my period this month and i'm spotting but it's like really dark brown and it's thick... idk what it is. i looked it up online and it's giving me different answers. have y'all had this? we're y'all pregnant? or was it just something that happened and didn't think anything of it. i had sex about a month ago. but i've lost weight so idk if i could be pregnant and i definitely can't afford to be pregnant in anyway. anything y'all think this could be?