I actually think that operating as a solo poly might work for you - if you can be honest with yourself and your partners you can "be in a relationship" (or relationships) and still "go clubbing, get drunk, and hit on girls."
You might want to read some of NYCindie (a member on this site) has to say about enjoying dating as a way to meet new and interesting people and have positive experiences without, necessarily, viewing it as an "audition" for a "potential partner."
I don't know that I would use the word "polyamory" from the outset - just let people know that you are interested in seeing them/sleeping with them but that you aren't interested in being "exclusive" and letting each relationship develop (or not) at its own pace. I do think that you might want to be VERY up-front about this to avoid the "hurt" that you have seen previously. I would advise being scrupulous about your sexual health (condoms always and frequent STI testing).
I look back fondly on my years of non-attachment - casual sex and "Friends-With-Benefits". I learned a lot about myself. When I fell into a relationship with MrS I "knew" that it was somehow very different - even though it started out the same way. I still like to "get drunk and hit on girls" though - luckily both of my boys are fine with this!
Me: poly bi female, in an "open-but-not-looking" Vee-plus with -
MrS: hetero polyflexible male, live-in husband (23+ yrs)
Dude: hetero poly male, live-in boyfriend (4+ yrs) and MrS's best friend
Lotus: poly bi married female, "it's complicated" relationships with Dude/JaneQ/MrS (1+ years)
+ "others" = FBs, FWBs, lover-friends, platonic G/BFs, boytoys, etc.
My poly blogs here:
The Journey of JaneQSmythe
The Notebook of JaneQSmythe