While looking off our balcony, we saw a stationary bright light that after a few minutes dimmed and started moving at increasing speeds

At 10:45 p.m., we were having a conversation in our living room. I then noticed a bright light in the sky, and we went outside on our 3rd floor balcony to see what it was.  
At first we believed it was a plane flying straight towards us, but we then noticed other planes in the air. This light was much brighter than anything we had ever seen in the sky at night before and much lower than any plane I’ve seen fly in our area. 
It made absolutely no noise and appeared to be two lights connected together. 
We grabbed my digital camera and took three pictures and one video.  The light kept its brightness and didn’t move from its original position in the sky for approx 4 minutes.
At 10:49 p.m., it began to dim, move left, and increase in altitude. Once it gained a bit of altitude, the object leveled off and started to pick up speed. It then began illuminating brighter again. We recorded this part on my Cannon digital camera.  
The object continued to travel leftwards in the sky and then decreased in altitude. It moved behind a tall building in the distance. At this point the object was the brightest that we had seen it.  It moved out of our vision while leaving us frightened and confused.