amped up---is a total slang for someone who is highly animated (due to drinking many cans of REd Bull , which is an energy drink with a high dose of caffeine). By the way, you are also correct ,it can include "getting one's spirit up".There can be several acceptable variations of what this phrase meas
D.J. is an auditory acronym and a contraction from the old US word Disc Jockey. A disc jockey is slang for one who originally played records on 1950's "TOP 40" radio stations (Top 40-being the popularity positions of songs of any specific time period).
D. J. is often printed DEE JAY, sort of a phonetic form of the word.