Spotting before stims

I was on BC for 2 weeks. My last pill was on 5/5. I’ve been a little cramping since Friday like when my period is about to start. I had intercourse with my husband this morning and when I hopped in the shower I see spotting. It’s not bright red but like a brownish spotting. Not sure if I should be concerned if I’m suppose to start stims on Tuesday possibly. Should I be concerned ? I go into the office tomorrow so I will mention it to them. Any thoughts ?