I'm so upset over this. Last night, my fiancée and I were having sex and all of a sudden as I orgasmed, I urinated and couldn't stop until my bladder was empty. It was as if I had lost all control of my muscles and couldn't stop the flow. The bed was all wet and smelled of urine. I was so embarrassed and shocked that it happened. Is this normal or is something wrong with me?

I think you may find some useful information in the following article:

Am I coming or going?: Distinguishing between orgasm and urination | Go Ask Alice! (http://goaskalice.columbia.edu/am-i-coming-or-going-distinguishing-between-orgasm-and-urination)