Thank you for writing JA with your question.
I see you already have had a urinalysis from your doctor. So, he must have not found white blood cells, which would have been my guess if you have not had that done already.
Another possibility is a yeast(candida albicans) infection in your bladder or elsewhere in your urinary tract. This is not always picked up on the urinalysis.
It is more common for women to have vaginal candida infections, and this is sometimes the route of infection in men. But this is not always the cause.
See: http://www.merck.com/mmpe/sec17/ch231/ch231c.html for discussion of yeast infections in males.
You might also be more prone to get this if you have been on antibiotics, which often creates an overgrowth of yeast.
It is possible to take a pill to get rid of this type of infection if other measures don't work
In the mean time, through out the rest of the weekend or for a few days, other things you can do are:
Drink up 8 to 10 glasses of water per day. If you don't like plain water, just put a squirt of lemon or lime juice in the water, but you don't want to drink fluid with much sugar, as this can encourage yeast. In fact, for people that get frequent yeast infections, sometimes they are found to have prediabetes. Cranberry juice is good, but buy the real unsweetened cranberry juice, rather than the flavored cranberry juice, and water it down rather than drink it all day. Cranberry has been found to help keep organisms from sticking to the urinary tract, so that they rinse out easier.
A supplement of vitamin C can help make the urinary tract less hospitable to these organisms as well.
Taking acidopypllus can help. You can get this by eating yogurt with cultures, or taking capsules. It helps your body's balance improve and replaces "good" bacteria, which is sometimes destroyed by antibiotics and for other reasons.
You can buy the lotion used by women for vaginal infections (generic name of one is mizoral) - you will find it in the femine product area) and apply it to the tip of your penis, if you feel that there is yeast in that area.
There are some yeast infections that are resistant to treatment. If this happens in your case, a treatment for this is Borox, which should be pharmaceutical grade and prescribed by your physician.
It may be that the above measures will get rid of any symptoms that you have. But if your symptoms increase or do not go away, I'd either see your doctor again or seek a second opinion, perhaps with a specialist like a urologist.
If you have any questions or comments, please reply so that I or another expert can answer them.