Fifties is definitely not my thing, but you've really pulled together some nice tones to fit that era! For 50s the hats are a bit bright, and I honestly think a completely mono mix might fit better...
There were a few performance issues from the bass (a bit ahead of the beat around 1:30) and drums (the break just before the solo it sounds like you weren't sure what to do on the drums and just didn't), but that also fits the "live" feel of 50s recordings. Your voice certainly fits the style. Couple of minor performance nits on the voice, too. But I doubt the majority of "normal" listeners (whatever that means) would even notice. Nice work!
Sorry for the political slant in this post. (Double spaces between all the sentences per the Opus/Bill platform)...