I do recall members saying their rabbits behaving differently when they (the owner) was pregnant so I suppose it is possible he is reacting to your homones..
But – I think it is more a coincidence of timing, personally. If his testicles only just dropped 2 weeks ago, it’s more likely a result of his own hormones coming in to full force! He’s likely feeling more comfortable in your home now also, and marking what he sees as his. 
Peeing on sofas and beds is unfortunately really common, especially with young rabbits.
Other then what you’ve done so far, you could try putting a litterbox up on the sofa while you are there. In the hopes he will go in that instead. Even if you just line it with a towel and pop a bit of hay in there.
Extras around the room may help too. If you see him lifting the tail or backing up into a spot, you can then prod him toward a litterbox or grab it and put it down for him. A little treat/reward after would help reinforce him using a box.
I tried looking on some rabbit vet list for your area but didn’t have much luck finding specific names. I did find this though. http://www.preventalitter.org/spay—neuter.html
There may be restriction on who qualifies to use a low cost clinic. If you don’t qualify, you could just enquire which of the vets does the rabbit neuters and if they practice elsewhere.