Sounds like you did too much, honestly.
I've had good results with fentanyl patches. Trick is to speed the release with heat. Be careful though, it's much easier to die this way. 5-10 minutes on with heat, 5-10 minutes off for an hour. Then be patient, wait awhile and repeat if needed. Use a heating pad ideally, but a blow dryer works too. Although it's easier to burn yourself with the blow dryer (trust me), so make sure that you don't over do the heat. Heating pads will burn you too, lol. The sickness/high ratio goes way up when you speed the release with heat, so take it slow unless you enjoy projectile vomiting.
Over doing it with fentanyl or combining other opiates with it never did me any good, and either made me sick or felt like a waste.
The buzz from fentanyl can be subtle one minute, and floor you the next. It seems to come in waves. But the line between high/sick is pretty thin with fentanyl, so I'm not shocked you felt like shit after adding heroin to the mix.
The key with fent patches is patience, it can be several hours before you even start to feel anything, even then it doesn't really get good til 24+ hours in IME.