My bf ate me out and he said he swallowed something...?

last week my bf was eatin me out and he said while he was doing it he felt something round and squishy in his mouth and he said he didnt think it was poo because poo doesnt come out of my v***** but im really worried about what this might be because my friends told me a story about a guy that accidentaly ate a girls sack of sti's and i dont think i have an sti but im scared thats what it mught be or it mught be a tumor. please help me!!!