Definitely fear but a bit of both I think. He told me he doesn’t want a child and I’ve made the decision for him because I don’t want to have an abortion (didn’t realise I could impregnate myself). I understand its difficult but for him but I know boys 10 years younger than him who stepped up to responsibly when they became young dads. It’s a shame because over the weekend he was excited, kissing my stomach, talking about names with me and now he’s just gone cold.
I know its really hard, my partner was exactly the same when our son was born we'd both just turned 20 & he was a surprise baby.
What ever emotions you're feeling, anger, disgust, hate, heartbreak they're all completely natural.
I know he says he doesn't want to be in babies life right now and naturally you want to protect the baby from that, but it could all change, keep that communication there, let him know when you have appointments, let him know if your scheduled a delivery or when you do go into labour, communicate it once, leave the choice with him. If he shows he shows, if he doesn't you have the proof that despite everything he has made you feel you have tried for your child.
Make sure he also pays his fair share, like you say you didn't impregnate yourself, regardless of how he feels a child is both parents financial responsibility, he needs to get his hand in his pocket and provide regardless.
I'm sorry your going through this x