Hi, It might be possible that you also have a mild case of epiditymitis or orchitis. (infection of the testicles). If your semen is clumpy and have a slightly red, brown color, it might be the result of the infection.
You want this checked out as repeated incedents can cause problems with fertility.
All the best
Ron
By the way, I'm 29yo, very good health and I drink lots of water every day.