Period after switching pills?

Okay so my pharmacy ran out of my orginal birth control so they switched me to a different brand which I took immediately after finishing my old pack, like normal. I dont miss days and Ive never been more than 2 hours late. The pills are combo and are the same dosage.

My boyfriend and I are very active and he doesnt pull out.

So, I switched and didnt have sex for like 6 days or so since I was on vacation. Anyway, Im on the 3rd placebo pill of this new brand and I was wondering if its nornal to have like brownish/reddish

blood/discharge at this stage? Its stained my underwear but its not enough for a tampon, just a liner. Ive been having mild cramps like usual but I was wondering if a "period" like this is normal or if I should be worried?

Thanks!!