Aaron Hernandez -- Gas Station Dance Party ... Before Odin Lloyd Murder

Aaron Hernandez was in one helluva good mood in the hours before Odin Lloyd was murdered ... dancing on his way into a local gas station ... and it was all captured on video.

The video was shot around 2AM on June 17, 2013 ... about 90 minutes before officials say Lloyd was murdered.

Prosecutors believe the video plays a key role in the timeline ... connecting Hernandez with the car that Lloyd got into a short time later ... the same car that was seen driving into the secluded area where Lloyd's body was found later that day.