Help with weird period!

Hi! New here and have a question regarding a very weird period (for me). My cycles are normally VERY regular and I'm able to keep track of it to the day via Glow. I'm a heavy bright red bleeder (6 days) with very bad cramps usually 2-3 days before I start. However, this month for the past 3 days I had my normal cramps but my period has been light red in a thick jelly like mucus, with some brown chunks in it. My bf and I had intercourse 2 weeks ago...I don't think I'm pregnant. Any idea what could be causing this? I have my annual check up in a couple weeks, but should I go in earlier for an emergency appt?