Freaked out!

Hello! To start off, first cycle of femara. I started on Friday (4/26) and was told to do so by doctor even though I didn’t have a period (mine are super irregular). I was told that would be considered day 5 for me (I take femara CD 5-9). I started light spotting just now like a period is coming and I am on third pill of femara! Should I be concerned, is this cycle wasted now or is this normal?