After I Ejaculate My Penis Feels As If It Was

After i ejaculate my penis feels as if it was clogged. Clear substance comes out a few moments before i ejaculate and after... My sperm has sometimes looked more clumped together rather then "string" like. Also after i ejaculate i will go to the bathroom to pee and my penis will have a burning sensation. The burning sensation would also occur if my pee was yellow. When my pee is clear is tends not to burn that much or at all. I have been tested and i came back negative in results of having an infection.