Ex “baby sat” our son

So I split with my sons father during pregnancy because he is and was a royal wanker. He was a great partner right up until I got pregnant, we actively tried to conceive, had ivf, but as soon as I got pregnant the true colours come to show, he tried to leave about 15 times, and always come back, and believed that it was my job to raise our son and not his, said he’d be increasing his work hours and doing overnight shifts so he couldn’t help during the day, so I left him, but agreed to co parent. Which lol has resulted in me being a full time single mum and he pops in for half hour at most once a week and video calls his son once every X months to say hi buddy and then have to run 5 mins later. His family want nothing to do with my son and have never met him, so whatever but I was at a hospital appointment last week and needed childcare it was on the one day he come by so I told him id be popping out and it could be an hour and asked if thats fine and he said okay no problem so great, he arrived 15 mins late so im running around like crazy and im getting my shoes on and he questions where im going, I tell him he already knows I have an appt and this motherfucker responds “what time is the baby sitter coming?” And I look at him like …. And he goes “im not babysitting” so I respond “IT. IS. NOT. BABYSITTING. IF. IT. IS. YOUR. OWN. CHILD” clapping my hands between each word and he says nah fuck that and walks out so I had to cancel my appointment and phoned him later that day to tell him if he cannot be present in our sons life then he cant be in it, he’s being selfish and our son is only 2, as he gets older hes going to wonder why you’re like this, so he told me he doesnt care and he’d be happy to never see us again, hung up and blocked me. This was 8 weeks ago, so I filed a court order to have full custody of my son, it got approved and he now has to legally pay child support which he never has before because he “was an active father”. He left me a 28 minute long voice Mail last night about how im ruining his life and he has no money because of me and he feels like im targeting him because I wanted a kid and he doesn’t. Piece of shit. Hope I bankrupt him.