I Was Out Drinking With A Friend And I Passed

I was out drinking with a friend and i passed out. While i was on the ground i was shaking. None of the above has happened before. I was tired and and have dealing with a lot of stress lately. I also do not drink much. Please help. Was i having a seizure? My body didn't ache. The next morning i had a headache. When he picked me up from the ground i snapped back into reality. From the time i collapsed til when he picked me up i did not lose my train of thought either. However i did not feel the impact of me hitting the floor. Please help