I had sex and i forgot a day on the pill

So I had unprotected sex a few weeks ago and didn't think anything of it because I'm religious about taking my pill at the same time everyday. Well I got sick like a week later with a cold and I took Mucinex for it. Well I took the night time mucinex and it knocked me out and I forgot to take it until I woke up in the morning. I took it when I remembered. But I was supposed to start my period on Saturday and I didn't start until Sunday and its been lighter than normal.

I guess I'm asking if this is normal