need advice

so even if i take my combo bc pill an hour late is it still effective? i’ve never missed a day i’m just a little late sometimes. my bf and i had sex and he pulled out way before he came not to risk it. i’m now on my placebo week and i usually don’t get it until the fourth day of that and it’s supposed to start in two days and i’ve been crampy and gassy and a little nauseous. idk maybe i’m so scared my body is just making my body think these symptoms are happening. could i be or am i overreacting?