SO wants a vasectomy after baby

Last night, after my SO and I had sex, we were cuddling. He looked down at me, and said, "So.... Those 6 weeks when you're recovering after having the baby, I was thinking about getting a vasectomy. What do you think?" I told him, "this isn't really my place to tell you yes or to tell you no. I know someday I'm going to want more children, but we're not married or engaged, so I can't really be angry if you get one, or angry if you don't. You never interfered with me having or taking my birth control before I got pregnant so it's kind of the same situation." He said that if someday, we want more kids, he can just go get it reversed.
Now, ladies, I know this right here is going to get a lot of judgement and probably make someone leave mean comments or whatever, but he's 30 with two children from a previous relationship.... I'm 20, and this is my first (his third). I've looked into vasovasectomies (vasectomy reversal) and it said they're not always successful and to pretty much not get your hopes up.
If he goes and has the vasectomy, am I giving up on having kids for the rest of my life if he and I would get married later down the line?
He was extremely angry and disappointed when I told him I was pregnant, and kept saying we ruined my life (I'm currently a senior in college and working a full time job. Got a head start as I graduated high school a couple years early) & the baby was a surprise to myself (I was on antibiotics and they messed with my BC, but I never once thought she ruined my life, as I've been excited since I found out, because when we first got together and things got serious, he said he never wanted more kids and to never bring it up because he wouldn't even consider it.
So here I am, hands tied. I can't tell him not to do it, because it isn't my body, but I'm terrified I'll want more kids 5-10 years down the line, and be shit out of luck... 😕