I'm a 20 year old guy. I work out, eat well and sleep at least 8 hours a night. when i was 16-17 I distinctly remember having way more morning erections and I was hornier in general,my erections were also stronger/bigger,even though I was watching more porn than I do now , eating worse and not even exercising. Its true I had a gf and now I don't.

Also the job I work at has pretty much no girlsthere so maybe that's a factor . In November 2017 when I last had sex I had trouble keeping it up and I came pretty fast. This was never a problem in the past. When i went out with a girl in March, we made out and I got an erection but it wasn't rock hard like i used to get in the past. I tested my testosterone levels and they were fine, a bit above average. I am really worried, idk what to do. I feel like I should be in my sexual peak right now.

TL:DR : Less libido ,weaker erections now than 3-4 years ago, even though I have healthier lifestyle. Help?