My 3 1/2 yo is displaying some of the same behaviors as your son. We finally figured out that he needs to use up some energy. Since it is winter we aren't as active. We plan something everyday - even if it is only riding bikes in the basement - to get more physical activity. So far it is working. Naptimes are still a little problematic, but we have no problems with nighttime.
My son also recently informed us that he would rather sleep on the floor instead of in his bed. At first we said NO, but told him we would discuss it, thinking he would forget about it. Not so. He asked the next night so we made a few rules, pulled out a couple comforters and let him sleep on the floor. It is now week 3 and he is still at it. He is sleeping well and abiding by the rules so I am willing to allow it to continue.
Another thing that might help is looking at your bedtime routine. Do you have a calming period before bedtime? Also do you work during the day? Maybe your son misses you. Perhaps spending some time alone with your son as part of a bedtime routine would help - pick out pj's together, talk about the day, read a book, etc.
Another thing that helps when my kids are upset about going to bed is letting them know they aren't the only ones and that there isn't anything fun happening to miss out on. We look outside and see that it is dark. We point out the street lights and say that when it is dark it is bedtime. We point out that there aren't any kids playing and that even the animals go to sleep. We look and listen and, of course, all is quiet. (I guess if you live in the city that strategy probably won't work.) Sometimes we call my parents and they tell my kids they are tired and are going to bed, too. Good luck!