Period on active pills?

Aleyna

I have been taking Alesse (combination pill) for two years now. I should be getting my period on Sunday (in 3 days) but I started spotting yesterday (Wednesday) and I’m still spotting. It’s like brownish blood and it’s not very heavy, but is is this normal? I did take my pill a little late last Sunday (I usually take it at 9 am but I forgot and remembered at 1pm) but I though that this doesn’t really matter with combination pills. I have never skipped a day