Am I in the wrong for being hurt?

So me and my fiancé have been together for over 3 years now, here recently I have noticed that he stays on his phone and protects it from me seeing. So last night I got the balls to see what was going on right?...well come to find out he must be a porn addict because his browser history was full of it. So I just kinda tucked it away. Today I went and got really sexy and was wanting to make it more exciting ya know? Well things went smoothly for a while but then he quit and was just got up and he was done...With out cumming...He said he was to tired.....my heart feels like it's been ripped out of my chest....I tried to talk to him but he gets very upset and try's to throw it on me like it's all my fault? So am I in the wrong? Or am I over reacting? Or is what I feel completely normal?