Postpartum sex aka hell

Our first time post baby at 6 weeks was actually really good but we've tried 3 times since then (I'm now 8 weeks pp) and it's so painful. It feels to tight and burns and I feel like I'm at max capacity when hes not even halfway in. I cant imagine why the first time would be fine but now I literally cry everytime we try. We've tried lube and it isnt that.