Is it possible to pregnant even when AF has paid a visit?

Hi ladies! Soo I know this will sound crazy. About 8 dpo I noticed some spot on my areolas that look exactly like pics of Montgomery's tubercles ( no joke, they're definitely not pimples). I tested at 12 dpo and got a BFN. AF showed up the next day, 1 day early. Now after being on AF day 4 they're still there, even multiplying. Has anyone else experienced this?? Are they reliable indicators? Could I still be pregnant?