I am freaking out. Please help

So last month i took plan b on January 21st, my period was a week early, it started Jan 31st. i started birth control right after that on February 4th for the first time after being on a break on it for 18 ish months due to pregnancy and breastfeeding.

It’s now the morning of placebo day (4)four. I haven’t gotten my period yet. I keep feeling like I’m getting it but when i check it’s just discharge. I did have sex February 22nd. But i take my pills religiously around 8pm. I’m on the combination pill and i made my husband wear a condom because I’m so scared of getting pregnant again. Is this normal? I took a pregnancy test yesterday. It was negative. I’m getting cramps (ish)

Could the plan b and starting birth control mess my period up? Am i pregnant? I thought this was supposed to be better but I’m still freaking out. Am i pregnant?!