Hi xraanswerban, since tests have given you the all clear, i would think that alcohol is the problem. i could do with more info, like your daily fluid intake, how often you urinate and most importantly, how is the problem eventually solved? however, i can tell you how alcohol could cause your symptoms. Alcohol impairs sensations, including internal organs like the bladder. it is also a diuretic, which increases discharge of urine. this leads to an over-distended bladder making it difficult or even impossible to urinate naturally. i would suggest training yourself to urinate at regular intervals when your drinking alcohol, even if you dont feel the need to. for example, after every pint.
you could always rule out alcohol by drinking just 1 pint or even a half, and then carry on your day as normal drinking your usual daily fluids,and see if there is any change in your urinary frequency, if all is fine, then you could up the amount the next time by a half or so, and see how that goes,
hope this helps, good luck!