I got some shampoo down my penis...?

Some time ago I was masterbating in the shower with head and shoulders shampoo (dumb I know now, but didn't at the time). I had too much in my hand and a good deal went inside my penis. The good feeling immediately went away and it just felt very cold. I still finished and then peed several times to try and get everything out. Ever since then though, most days it doesn't feel the same. I used to feel really horny all the time, but now not as much. Everything still works, it just doesn't FEEL the same, like not as good. I'm afraid I did some permanent damage or something. Does anyone know if this is possible? Is there any way to fix it?