So I'm not on any birth control and my boyfriend told me he's infertile after a childhood illness but I was late on my period by 3 days and I just looked up the chances that his fertility could have come back because I'm scared of getting pregnant and didn't know whether I should go on something to stop that happening. 

I feel like a dick for typing that into Google. Yesterday my boyfriend was using my phone and opening the tabs on my browser. I'm not sure if he saw but then I snatched the phone off him, he joked if I was watching porn and I just laughed but I'm sure he looked over and saw it because he just said 'oh'. 

I have nothing to hide from him but now feel like I'm hiding something from him when I'm not and I'm not sure how he feels about it. He's acting normal today and kissed me and the usual stuff but theres that itch at the back of my mind that keeps telling me that should be worried, I've done something wrong, how dare I not believe him when he tells me he cant have children. How insensitive of me to even look it up? 

What do I do? Do I talk to him about it? Do I just leave it and wait to see if he brings it up? Is this as serious as I'm making myself believe it is? 
I'm filled with so much anxiety and I cant cope man