Alcohol affect on me

A couple months ago I was drinking about 4 shots of vodka and I got boarder line drunk and was very tipsy. It took about 1-2 hours for me to be able to act normal. A couple weeks ago I was drinking and I had about 3 shots and it took me about the same amount of time to act normal again and in the morning I didn't have any side affects besides dehydration and sore legs. Then yesterday I drank maybe 3-4 shots and it took me forever to sober up and act normal took about 3-4 hours and no side affects this morning and I found that really weird and has anyone got any ideas why it took so long?