Beyond stress and need advice or perspective

I’m lost and confused on what to do. My baby daddy and I have no court orders, and Idk what to do. He’s suppose to have the kids every weekend from Saturday around 5 after he works until he’s suppose to take them to school Monday morning. He gets his kids 2 days a week basically. Now we are young, we are 21 years old with 3 kiddos under 2. It’s frustrating because I work as a realtor, I also take care of the kids besides those 2 days. He constantly attacks me saying “you don’t think it’s hard on me to not see the kids I cry every night and you throw it in my face that you have them more” and I’m really not trying to. I just try to explain that he gets those 2 days and the girls love it! He’s flaky. The whole time he has them he calls me asking what I’m doing and then will find a way to be like “oh I’m to tired for the girls I’m bringing them back so you’ll have to come home” and if I’m not home he will leave them with my parents and he thinks my parents help me 24,7 and yes they help but I still work full time from home with the youngest and take care of the house. He says that “he doesn’t have a life and it’s not fair that he doesn’t get to go out with his buddy’s because he has kids.. but I get to go out (like once every 6 months) but he works 5 days a week, with no kids and he gets mad and I just don’t know what to do. He also only gives me $100 a week for 3 kids and idk if that’s normal? I’m just lost