can't afford plan b

So me and my boyfriend had sex yesterday and it was great. I just got off my period 2 days before. But anyways today I get a random text from him. Stating did u take a plan B because babies might be on the way. And I'm like why didn't u tell me that u came in me. Long story short I need help!!! No judgement comments please.   Can't afford a plan be at the moment so can I take 5 birth control pills or something. Someone help. My boyfriend just all of a sudden hit me with bs