Hi,
You seem to be having some infection, it is better that you and your partner together visit a urologist for a check up.
Solace
This may not be semen. It could be puss from a urethritis. You need to have this cultured and go on appropriate antibiotics.
Is this called yeast infection. The colour of the discharge is getting darker. Any idea what it is called? What kind of antibiotics should i get?