I hope my swing hasn't fallen apart!

Right.... I've been playing for about a year although my swing was all wrists before I had 5 lessons over the last 3 months. During the lessons we worked on me turning my body and commiting to the swing etc.....

 Over the last month I've been playing some great golf and have been hitting the ball consistently however last weekend I played 3 times... my swing and contact got progressively worse across the weekend... resulting in me shanking every other shot in the last round of the weekend.

 Any Ideas? admittedly I'd had a few beers the night before the last round and I personally think i've just not been commiting to the shot and finishing with my hands high enough. I really dont want to fork outy on more lessons just for him to tell me stuff I already know so should I go back to practising what he first showed me and work my way back up from that?