Clingy

Jacob is going through a new stage where he has periods each day where he is super clingy, and I'm not quite sure what to do.  He play's great by himself for the most part, but as soon as I get close or come over to him he crawls over to me, pulls himself up to standing and has a complete meltdown if I try to put him down again to play on his own.

I know babies go through different stages, but I'm having a hard time figuring out the right "parenting" approach on this one.  Adam's better at the tough love, and when Jacob does it to him he can leave him to cry and within a few minutes he's usually happily playing by himself.  Jacob knows I'm a sucker for him crying though and when I leave him to play on his own during these times (usually when I'm trying to get a few things done around the house) the crying does not stop after a few minutes!

Part of me wonders if it's because I had to stop nursing him do to my milk supply (I still nurse him once a day but it's not for very long) and he misses that bond, another part of me wonders if my midwife is right and that he knows that there's another baby on the way and he can sense change is coming (apparently research has shown a significant change in a lot of babies behaviors when mom get's pregnant), and then part of me wonders if it's just a stage and I need to get over myself (although what that looks like I'm not quite sure yet).  I feel frustrated at myself for feeling frustrated at him for being in this stage...  and the guilt that follows that doesn't help either:)

So do any of you have any words of wisdom of how you dealt with this with your little ones?