Sorry for the delay, there was a lock on the question for 5 minutes that I could not remove.
Of course you need an exam and testing to say what this is.
Given your details, possibilities are
Prostate irritation [oven happens from sex.]
Prostate infection flairing up.
Infection of the urethra.
STD from the new partner, trichamonus and others.
Not std from partial hand job.
OK, so let me know if you have more questions.
Also, please click a positive rating on the rating scale. In fact, a 5 rating squares me with just answer and allows me to provide prompt and accurate service to you, but does not increase your cost. And, I will be here for any follow up needed.