My first time sucking the dick😗

Okay so.... I was with my boyfriend and I was giving him a handjob. He was getting really into it so I thought, “girl just go for it”. And so I asked him if I could and he said yeah so I started sucking his dick. (First time of course) so like I was trying to use my tongue and sucking and I was using my other hand and he was liking it. Then he said ok stop and I was like “well do you wanna finish off?” And he answered “well yeah” so I kept sucking and he did finish off in my mouth but my dumb ass just swallowed a little and then I took my mouth off and it just kept coming and it got all over him and my arm. So I felt bad and I felt like I didn’t do a good job and ugh. I was kinda mad at myself but he was like “are you kidding me?!” And laughing cause I was dissapointed in myself. So he kept saying it was good but I feel like he was lying just to make me feel better. Ugh help? Peeps?