Erection trouble in 20s? Idk if it's mental

Early 20s, gonna be intentionally a little vague. Overweight/Fat but used to be obese. Abused weed which led to obesity, inactivity, etc. during that time and had issues staying hard during sex with girlfriend, would start to fade after a minute of penetration.

I've lost 30lb+ pounds and counting, no longer smoking, active lifestyle, and not watching porn/self pleasuring. I was never really into porn, and also wasn't always high during sex, so I think issue might be mental?

I still have a high sex drive, and when I'm with a partner I'm super into it, usually even have trouble lasting if she's giving hand/blowjob, but it seems like my only paths are to go quick or soften up during penetration.

Has anyone else had issues with this? If it's mental or common, I'd like to avoid using medication like Viagara at this age.

Edit 1: for more context: I'm working with therapist for my other anxiety/mental health issues like depression, but idk if there's specific sexual anxiety people. I've had limited sexual partners so I also get anxious that I'm "performing well" when I'm with partners