After ejaculation I notice I have? A harder time urinating for about 10 minutes?

This is normal. Bladder neck closes so that semen is propelled down the urethra rather than backwards into bladder (retrograde ejaculation or re) it is then quite normal for bladder neck, comprised of involuntary muscle, to relax ; open up in oder to allow urination to take place. Re can be normal after prostatectomy because bladder neck is enlarged especially after trans-urethral resection (turp).
Pretty normal . Some men experience this problem. It may be due to a swollen prostate that gets less swollen after a few minutes. Most men can not urinate with an erection. Once your erection resolves, you should be able to urinate without difficulty. If not, call your doctor.