What is the deal with the nesting instinct and is it indicative of impending labor?

I lost what I believe was my mucous plug over a week ago but didn't think much of it because there was no blood in it. I heard it doesn't usually mean labor is soon unless there's blood in it (bloody show). Then,about 4 or five days ago, the baby dropped. It was very obvious difference in my abdomen. It has gotten much flatter at the top. I can breath easier now and my heartburn that had been so bad before is almost nonexistent now. Plus there is a definite increase in pressure in my pelvis. Yesterday evening i think i started nesting. I all of a sudden felt the uncontrollable urge to clean and further prepare for the baby. I had energy as though I was on a very effective stimulant with no crash. My husband wanted to watch a movie we rented and I couldn't stop cleaning. I even refused to stop and was glad when he fell asleep early so I could get up and do stuff. I don't recall feeling that good in a long time. Could this have been nesting and does it mean labor is coming,possibly when?