Oh, can I relate. My DS6 is VERY sensitive. He was "diagnosed" with Sensory processing Disorder when he was 4 but there were other things we noticed that made us think maybe the diagnosis wasn't entirely correct because he never seemed to fit the descriptions....he's not on the autistic scale or aspergers - those have all been ruled out by several people. When we met with a psych a few weeks ago to do the RIAS and Woodcock Johnson she informed us that she really believed he did not have SPD but that he was HG and had OE issues. We are really beginning to see that that description seems to fit him MUCH better.
His newest thing is that a few months ago when we were in Lowe's and I was checking out something on a shelf, he was messing around with something next to the cart. When I looked, I noticed he had run his hands through a spilled bag of purple pellets - 'joy' - ant poison pellets. I didnt freak or anything, just told him that we needed to go back to the bathroom and wash his hands off. He asked a million questions about why and what would happen. I tried to explain that everyone just washes their hands after touching things like that. I realized that I have always really been open about letting him explore/touch things because he is a hands-on, kinesthetic learner and rarely tell him no when it comes to touching something...well we are now dealing with him being afraid of touching things. He takes things VERY literally and tends to worry now if he has touched something that he shouldn't have. He refuses to go down that aisle at Lowe's anymore and freaks out if we come even close to it.