Growing pains...

So after being gone for 10 whole days my son Seth has surprised me with some interesting changes... He no longer sleeps through the night; I mean not even 4-5 hours at a time, after 3 hours he's up and ready to eat. Another change is that now he wants to be entertained... a lot. The biggest change is that he is very finicky about his bottle. Sometimes he wants milk sometimes he doesn't and he is very adamant about the times he doesn't want it. Yesterday I thought I could force him to take it, I knew he was hungry so I kept insisting, but so did he, the more I'd try to give him the bottle the louder he'd scream. I kept at it for at least 5 minutes, but eventually he won out. I did however find a trick to it today! The trick is to make him think he wants the bottle.  For example; if I give him the bottle and he spits it out, I try again, same thing happens, at this point usually the tears would start, but now I just sit him up on his bottom and then show him the bottle kinda give it to him to hold, within a few seconds he puts it in his mouth and starts drinking. If he really isn't hungry this doesn't work.
I don't know why all these changes.  I so have some thoughts on why they are happening but not for sure why and what needs to be done about them, if anything even needs to be done. My guess is that some of the changes are due to normal development and just plain growing up. Some of the changes are due to the fact that when he is at his grandparents house he gets spoiled and if he cries at all he gets attention, so now he thinks that he is the most important one in the house (which of course he is, but I don't want him knowing this already). :)
I am concerned about the sleeping situation I thought we were on our way to sleeping through the night, but I think all the changes lately might have him a bit discombobulated. I'm gonna give it a couple of weeks and see if things fall back into place if not something will need to be done about improving our sleeping arrangements.
On a fun note... today I went shopping with him and we got a few really cute outfits and four new hats... he had so much fun at the mall. He seems to really love people watching. He smiles at people walking by and especially at those that stop by to say hello. One time today a lady was telling him what a cutie he is and he was smiling from ear to ear when all of a sudden he stuck out his tongue at her. We both cracked up. I told the lady, that's his way of saying he likes her... ;)
Here's the photo shoot from after the shopping trip.