Struggle to be into sex

Me and my girlfriend have been dating for about 2 years now, and I love her very deeply and she feels the same way. I have had erection issues due to anxiety throughout our entire sex life, we are both eachothers firsts, and she is extremely good at pleasing me as well. But I just cannot get anxiety out of my head for the love of me. It bothers me atleast half the day theres the feeling that I will disappoint her yet again. We have had sex so many times, 3 times last week but just one minor slip up and i'm all in my head again unable to even perform basic functions. I've gotten blood tested and have no hormonal issues. This anxiety seeps through my entire life and I am so attracted to her, and I feel so terrible.