Tramadol isn't dextropropoxyphene (darvon, darvocet). Its tramadol (brand name ultram). On top of that, dextropropoxyphene is complete and utter shit as an opiate/for recreational use for most every. Somebody with no tolerance might be able to get some pleasure out of it, but someone with no tolerance has no need to use needles in the first place. Also, dextropropoxyphene has a low therapeutic margin and all sorts of toxicity, especially concerning the heart. Its a shit drug and I advise nobody take it, let alone inject it.
Anyway, the OP has tramadol. I personally enjoy it, but many don't. Its a very atypical opioid. All I can say is read up on it and see for yourself what you think about it, and if you want to try it. And if you do, start small. I don't know how much stronger it is when injected compared to when taken orally, so I don't know exactly you'd want to inject, but if you have no opioid tolerance I'd say start with 50mg to see how you tolerate both the opioid effects and the serotonin releasing and epinephrine reuptake effects. These could easily make you nauseous, or worse. If you can tolerate that, and aren't yet high, try another 50mg. If you have an existing opioid tolerance that all goes out the window though, it could take much more, or if your tolerance is high enough you could get next to nothing from it. I don't feel like typing anymore. Hope I've helped.