idk if I wanna be with him anymore

Valerie
So I'm 5 weeks pregnant. And honestly every week my bf been asking me for $200. I feel like he uses all his money on weed then he runs out and asks me for me money or pay his insurance or rent... he knows I'm going on vacation for 3 weeks and leaving on Friday... so today he picked me up from my house and it was raining went to oriellys cuz he needed wiper blades for his car... we get to the register looked at me and told me to use my card.. I was embarrassed so I paid it.. I said fine I'll pay this but ur paying my groceries when we go later before u drop me off he said ok of course... so we watched the football game at his house he made dinner and we go get groceries and go to the counter he looks at me tells me to use my card... I was so extremely pissed and idk if it my hormones or what but I was furious and he goes ur mad over $20? Technically it was $50 but I didn't say anything. He said just take it out of the $200 ur gonna give me this week... I was pissed... he parks in front of a Bank of America before dropping me off and asked me for the $200 since I'm leaving on vacation Friday... I took out $160... but whatever... idk what to do... I feel he's never going to support me and I'll be forever making the money and he'll use all my money or money for the baby all on weed or watches... idk what to do... should I just leave him since he'll never be able to support me and our child or am I just overreacting? 
Update:
I am now gonna be 9 weeks pregnant... and I left on vacation for 3 weeks gonna be coming back home in a couple of days.. he asked me for money again while I was on vacation saying he has nothing so I put my foot down and said I wasn't gonna help... he recently messaged me saying he figured it out don't need my help.. now he's saying he's not gonna see me when I get back cuz apparently after being let go he found another job graveyard shift 7 days a week... bullshit! No job will make u work 7 days a week... I'm not buying it... yup he's acting like a baby because I'm not helping him no more.. so I ended it with him.. so I guess I'm going thru this baby thing by myself... I'm really sad it sucks.. but I know it will be a better life for me and my baby. Hoping this depression changes once I really get to c my baby on dec 3rd at my next ultra sound. Also, I thank everyone for their replies, makes me think how stupid I was. I can't believe I was doing that. Y'all really opened my eyes. Well I def have learned my lesson. Since I was supporting that big baby.. and now that he's gone I think I know I can support my actual child. I think I'll be okay.