Trouble breastfeeding

So when LO was about a week and a few days I ran out of milk. I had to supplement because LO was screaming bloody murder from being so hungry.  LO is 3 weeks old as of yesterday and since then I have been pumping and giving him the bottle. I've been attempting to get him to be on the breast again and it's a struggle. He won't latch properly and also gets mad because the flow isn't as fast. Anyone having a similar problem? Any suggestions?