Liver enzyme elevations are not an expected side effect of Diphenhydramine
You mention you drank alcohol a month ago. If you were drinking on a regular
basis before, it is possible that your liver enzymes could remain abnormal
especially ALT,GGT, not so much the LDH & SGOT.
You also mention that you are on a low calorie diet. You must be doing this
to lose weight. If you are 10-15 % overweight
, it is possible you may have
Get a complete liver profile, blood count,diabetes check, and also screening
for Hepatitis B
If you are on any other medications such as Ibuprofen,Naproxen (NSAIDs) , they
can cause liver damage
Hope this helps you so that you can discuss with your doctor.
I wish you well.