Definitely, stress can create a situation in which erection is harder. What's going on with the stress? Any way to make that better? You've been to a urologist and had testing or no? This article talks about stress and anxiety and how it can negatively impact your erection https://www.healthline.com/health/erectile-dysfunction-anxiety-stress BUT, you want to make sure that you've ruled out other things first. So, you have to talk to your doctor about this.
What did the urologist do who said your prostate "seems ok"?
It seems like it isn't, so I'm wondering if the urologist did an exam of your prostate, did any blood work, an ultrasound, etc?