Fiances mom pissed off

Ta

So, we went over to my fiances parents house, and we told his mom we were getting married. An she dropped everything she was doing and looked at us both with the most evil stare, and said "why?" And he goes "why not? We're in love". This lady starts going off, telling us how we're so young, and we haven't even lived our lives yet, and saying how we're not ready for any of this. And then she looks at me with a glare of pure bitch and says "are you fucking pregnant" and I said no ma'am. So moral of the story she was pissed and everyone else was happy, we don't know how his dads reaction was cause my fiancé just walked out and he told me to follow him, we didn't even say bye. So now I'm stressed out. I'm 18 and he's 19, and next year we'll be 19 & 20 by the time we get married, and we've been together for 3 years. The rest of my fam was saying how they're surprised it didn't happen sooner. But idk. Sorry for the long rant, I'm done 😂