Uncomfortable feeling on penis

I am 22 years old.

• I constantly experience a feeling similar to muscle strain / very mild pain / tired muscle at the bottom of my penis (Bulbospongiosus muscle).
• I constantly have uncomfortable feeling at the tip of the penis (urethral opening) where I feel urine is not fully released and stay in the tip of my penis.

I don’t think I have feeling of full bladder. But these uncomfortable experience make me visit toilet frequently, try to release the urine, and only urinate in small amount. The uncomfortable feeling sometimes temporary go away shortly after I urinate.

• Sometimes when I urinate, I experience some sort of penile muscle reflex that hold my urine.
• Sometimes I feel pain in the urethral opening after having wet dream. The pain go away in a few hours.

These are all the abnormal experience I noticed. The color of my urine is normal, there is no any visible bleeding. I didn’t receive any special medication or consume any sexual enhancement drugs.

I hope doctor can help me find out the source of problem. Thanks.