38 yrs old what is going on?!!

S

What is going on? Im 38 and on cd 16 on a normal 28 day cycle. I felt like i ovulated early (cd10) and had sex on that day ( however SO didnt finish) but couldn't tell you about precum not sure. So If i did O early on the day i think i did the yesterday would be 6 dpo and im having brown spotty bleeding. This is the first time ive ever had bleeding in between cycles. Perimenopause, implantation, period?? What are your thoughts?