Difference between Ultram ER and Darvocet?

I had broken my wrist back in April and the doctor prescribed me Ultram ER, in which I got EXTREMLY sick from... To the point I had to go to the hospital and I was throwing up for 32 hours! I just took one 50MG pill. Had a bad effect on me, which I went to the pharmists and he said that is pretty common with it, I guess hes heard of it having bad effects on some people. Since I was a little girl I get migraines and was prescribed Darvocet for them. I have tried some other medicines when I was little and they never seemed to help. But I am sooooooo afraid to take a Darvocet after my experience with Ultram ER. I never wish the illness that I had with them upon anyone!!! It was bad... LOL So basically I wanna know what the difference between Davrocet and Ultram ER is? And I know that Ultram is Non-narcotic.