How do I treat my performance anxiety?

Hi!
So I have an issue that has been lingering for quite some time now. Every time when I feel like I am going in the direction of having a sexual encounter with someone I turn it down because I feel like I will only disappoint them since I feel like I won’t get it up.
I remember when I was 16-17 and I used to make out w a girl I would get hard just from that! But once a girl made a comment about not being able to feel my erection through my jeans and since then I haven’t been the same. Constantly overthinking and now I have trouble getting it up.
I am definitely what is considered a “grower” and so it become much more embarrassing for me when I can’t get it up, I just don’t want her to even try and get be hard because I feel like she will judge me. Does anyone else have this type of feeling?
How do I deal with this? It is normal to not be able to get hard when simply making out? I’m in good shape, I play basketball semi-professionally so I know it’s not a physical thing. Also when I’m alone I can get hard.
So why is this happening? How do I get over this fear or being too small or not good enough? Mind you I haven’t gotten any complaints so I don’t know what’s going on in my mind!
Please help, any input would be helpful :slight_smile: