I'm 3 years post op, and my period is only back on track for about the last 8 months. WLS causes your body to go into shock, hormone levels go up and down and therefore you might suffer erratic or lost periods for some time after surgery. Your body needs to adjust and reprogram itself. Give it time, don't stress about it.
WLS defiantly altered the way my body processes alcohol. I had quite a strong constitution pre op... But not anymore!! Two glasses of wine and I'm ready for bed these days. So I find I don't really bother much, it's not enjoyable and the hangovers are a killer!