I think that you may be experiencing the beginning of penial nerve damage. Any strange feelings from below the belt is serious stuff if you value your sex life. You need to make sure that your saddle is the right size and positioned correctly, and you might want to discuss this issue with your doctor.
To ensure that you have the right saddle size, measure the distance between your sit bones. They are the boney knobs in your posterior that bear your weight when you sit down. A good way to do this is to take a peice of aluminum foil, place it on a carpeted step, and then sit on it. When you get up, you will see two impressions that are deeper than the others. Measure the distance between these impressions and that will be the distance between your sit bones. You need to have a saddle that is wider than your sit bones, otherwise you will have soft tissue filled with nerves supporting your weight. It is too easy for these nerves to suffer compression damage from supporting your weight.
A level seat is just a starting point for adjusting your saddle. If you are putting weight on your tender bits when you are in the saddle, not only are you compressing your nerves, you are also decreasing the blood flow. It is OK to slightly tilt your saddle forward to relieve pressure, but not so far that you begin to slide forward when you are riding. Also ensure that your saddle is not raised too high as this will cause undue pressure also.