Long term femara advice

Hey ladies

This will be my 5th round of femara and it has gone good so far other then this month.

Background: prior to starting periods were irregular and diagnosed with (thin) pcos

Started taking femara low dosage then month before last I did a higher round, which didn’t result in a pg so last month I went back to lower dosage.

The ending results came back to me spotting 5 days before my period and I mean light spotting and now my period is late by 12 days. Took a test on the projected period day and was negative. I don’t feel pg so what you guys think is going on?

Can’t see my doctor till next month to discuss