Late period

Just a general question, my husband and I have been trying for over a year to have a baby. We’ve met with a fertility specialist who put my on Folbee & 81 MG EC aspirin. According to the Premom app, I’m 4 days late and according to this app, I’m 2 days late. I took a test this morning and obviously negative (picture below). Is it possible that the medicine they have me on could be messing with my cycle?