What would cause normal looking ejaculation to change to watery, yellowish semen overnight?

I have always had normal creamy looking semen until a 2 weeks ago.  I had unprotected sex with someone where I had received a ********, and then masturbated afterward, which when a ejaculated everything was normal.  However I noticed the sudden change the next day when I masturbated.  When I ejaculated it was not the normal creamy looking semen, but watery and with a lite yellowish color.  I did not have any pain, burning sensation when ejaculating or urinating, nor does my semen have a strong odor and i have not had any unusual discharge, which are the signs of a bacterial infection.  I have masturbated 6 times since then and still with the same result.  I thought it would, after time, go back to normal but it has not and I am starting to get worried.
The pic is taken immediately after ejaculating...it came out watery and with a lite yellowish color...

[Bhupinder Kaur, MD]

Hi,
In view of the lack of any symptoms suggestive of a sexually transmitted disease, I presume everything is fine and nothing much to worry. The changes in the consistency of semen can happen with the changes in our drinking behaviour. If we consume a lot of fluids, the semen tends to become thinner and in the case of consumption of less fluids it tends to become thicker. Moreover, frequent masturbation can also make it thinner as it doesn’t get the time to become concentrated. If y wait for a 2-3 days and then masturbate, I hope the consistency of the semen will change. I sincerely hope that helps. Take care.