Did the Provigil/cialis Combination Harm My Penis?

I am a 41 year old married male. I have an active sexual drive. I'm not taking any perscribed medication, nor am I a drug user. I stopped doing drugs about 3 years ago. I don't have any major health problems except sleep apnea, which I use a cpap machine to treat.

Last new years I took a combination of medications. I took a provigil, my wife's narcolepsy medication, to help keep me awake all night. I also took a cialis to help extend the nights fun. We got back to the room at about 3am and we're having sex until about 8am. I know people brag about this and you guys discount them immediately, but this really does happen. Later that day I noticed a huge (about dime sized) blood blister looking thing, under the skin near the head of my penis. This has never happened before even though I have done the same combination of medication and sex time before. It wasn't really painful, but took weeks to totally go away. Afterwards the skin was rough to the touch where the blister was. Eventually it went away. I assumed it was the cialis and vowed never to take it again. I've gone out and partied since then without taking anything and haven't had a problem except being sleepy.

This past halloween, when we went out I took a provigil to help keep me awake, and the same blood blister thing appeared again after sex! Actually this time it was very difficult to even keep an erection. Since then, I have been sick as a dog with this latest flu/cold and working my butt off, but I have yet been able to have intercourse with my wife. I just can't keep an erection. I'm really worried, but more embarrassed to go to the doctor. I hate going to doctors, especially about this, and dealing with the cold insensitive administrative and medical staff I see at doctors offices.

What could this be? Did the provigil cialis combination harm me? Do I have a blowout in my penis?

-worried...