Old blood ?


So I’ve noticed brown blood when I wipe/on my underwear. It’s been happening for a few days now. Been having small cramps and low back pain. Nothing major. Haven’t had sex for months. Very Irregular periods; can go months without it. Is it just old blood cleaning out?

I usually sync up with friends/coworkers and I did see one of my friends last week who was on her period. Maybe that’s why It’s happening?