If you are certain about saddle, fit and chamois cream, I would definitely do two things.
1) make an appointment with the dr to eliminate any possible nerve issues or infectious or bacterial issues.
2) I would also consider it a strike against the shorts, especially if it is a pair that you don't wear often. Every brand fits differently and chamois thicknesses vary. Even in the same brand and style, the fit can be slightly different. If you find a pair/brand that works without rubbing, numbing, chaffing, chamois being too thick or not thick enough, etc. invest in a couple of pairs and figure that after a couple of wearing one or more of them may possibly cause problems. I keep a permanent pen around to mark an x on the tag of shorts that give me problems. Three strikes ( one for the shorts being faulty, one for the fact that I may have been sitting wierd that day, and one for an act of fate) and the shorts go.
I keep a permanent group of 4 good pairs of shorts plus possibly another 4 with varying number of x's on the tag. When one pair gets tossed, I go out and buy another. I could function with fewer shorts if I had to, but I tend to do a lot of long distance and touring so I need the flexability of not having to wash every day. But that's just me.
I also find that if I haven't ridden for a while, down there is generally a bit more tender and sensitive.
See the doctor and feel better soon.
marni
Katy, Texas
Trek Madone 6.5- "Red"
Trek Pilot 5.2- " Bebe"
"easily outrun by a chihuahua."