My parents are making me feel really uncomfortable - puppy drama

My boyfriends dog was in heat. My mom “accidentally” put my brothers dog and my boyfriends dog together. Of course she got pregnant. So there’s 6 puppies. My boyfriend (since it’s His dog) said his sister could choose first. My parents FREAKED about “first pick of the litter because their dog was the dad” again, it was an “accident” and unwanted by me and my boyfriend. So then they choose a puppy and my mom wants another one. My stepdad told me he wanted one for my mom to be a surprise. I told him today that I couldn’t give any away for free, because there’s a rehoming fee, that even my boyfriends sister has to pay for. Now my stepdad is making me feel uncomfortable by saying “oh that’s ok, we don’t charge much for the stud fee”. Acting like I’m going to pay them because their dog got mine pregnant? We just don’t have the money to recover from buying all the food and shots to give puppies away for free. What do I do?