Hey Dan --
I know the feeling! I had a dull ache in my surviving testicle too after my orchiectomy and it reminded me a lot of the ache I had before I got diagnosed. I freaked out and went back to the doctor and had another ultrasound and of course, I was fine. I posted about it on this forum and the pros here gave me good advice (as always) which is that TC is pretty rare in the first place, and getting it again in your other testicle is even rarer than that -- especially so close to having it the first time. I'm not sure why the ache happens, maybe your testicle has to work harder to make up for the one you lost?
Anyway, if you're on surveillance, maybe you can mention it to you dr. the next time you're in, but I think if there's no change in the way it feels or the size then you're probably just fine :-)
28 years old
New York City, NY
Ultrasound on 1/23/12, I/O on 2/1/12
Classical seminoma, 4.5cm, RT invasion, LVI, no spermatic cord margin invasion.
CT scans clear
pre op bHCG: 57, post op: 2.4
Clear: 5/17/12, 8/23/12
11/29/12 -- CT scan shows 1 enlarged retroperitoneal lymph node 20mmx15mm, stage changed to IIA
12/17/12 - 3/17/13 -- EPx4 @ MSKCC
Clear: 3/7/13, 3/28/13, 5/2/13, more to come...