The AST could be high for other reasons (exertion etc). The ALT is more liver specific. Dr. usually are not too concerned until the readings are in excess of 2X the upper limit. But if your AST/ALT come down after abstaining from alcohol for a week or so, then it is pretty sure that the alcohol is the cause. If so, then the amount you are drinking is too much for you.
Elevated enzymes mean cellular damage. Cellular damage means the body tries to repair it, which can mean scarring. Scarred liver tissue does not function well, if at all.
You're still young enough to avoid being 50 years old and yellow. Limit the drinking to a few pints a week and never more than 2-3 on any one occasion. Above that and alcohol becomes toxic. And the best part of only 2-3 a week................no more hangovers.