Used to get Harder

It’s something that bugs me a lot. I won’t get into details, but I used to be able to get significantly harder than I can now. Making out with my girlfriend, I got a lot bigger down there than I do now. I’m pretty young, and that was as only a couple years ago; there should be no reason I’m having this trouble, especially when I’ve been dealing with my porn addiction and improving on it for a while now.

I’m not looking for vague “porn’s the problem” answers. If anyone knows any research or personally deals with this, had this happen to them and it got better, I’d appreciate hearing what I can do. Thanks