After a really long night of drinking, is the next day like really depressing?

i feel like i just did ecstasy and all of the serotonin in my brain is gone. last night i was really drunk, and it isn't like i was rejected by friends or girls, if anything it was really great... but i got home today and all of the sudden i just got really depressed and lethargic feeling. i am also not new to drinking, but i have never felt this depressed. i am also not tired enough to be acting depressed. what is wrong? what should i do? i almost feel ignored by everyone around me even though i am not at all. not to toot my own horn, but i am kind of the toast of town. why am i depressed?