Car: 1999 Honda Civic Si

Problem: I was driving home from work the other night and as I was signalling to change lanes, I noticed my headlights flicker. As I went further down the freeway, I changed lanes again - this time changing lanes in the opposite direction to see if they would flicker again...sure enough they did. When I got home I was sitting in my car with it parked and with the parking lights on and I pushed the power window button and my gauges flickered with the same reaction as the headlights did on the freeway. I dont know what this could be. Any ideas?

Side note: The car has a remote start installed on it. It is currently disabled, (or I just dont know how to use it correctly) but Im thinking for some reason its possible that there could be some electrical interference with the flickering problem. I got my battery and alternator checked, and they both checked out fine. This isnt a major problem, but I would like to figure it out and fix it so that its doesnt evolve into anything else.