Brown? Help!

Emma • I`m honestly so confused about my period and vagina
During the mounth of May (the first week) I got a "period" but no cramps or pain, just brown mucus (?) that is very light or medium with occasional blood. Is it a period? 
I had it again (the end of the same month) and its brown, light, and a bit of blood. 
What is this?
I heard about implantation bleeding but it's been two months (at the time, May) since my boyfriend and I had any serious dry "play time." We only dry hump (he's in boxers or gym shorts and I'm in panties) 
I have really irregular periods to start with too