I agree w/gamom. I think all you have here is a serious case of yesthisisallnormal! Even the being confused. Trust me, that is very normal and never goes away. I wish I could tell you it all becomes clear at such and such point, but in my experience parenting in general is confusing. Sigh.
Smart to pump to give yourself a stash for when you return to work, but don't expect to be able to pump what you will once you are pumping while back at work. Right now you have a growing baby drinking up all (or anyway most) of your milk all day and so anything *extra* you can pump is good. You know that what a mom pumps is a very poor indicator of what her actual ‘supply’ is, this is so important! So many moms let the pump output freak them out unnecessarily. Again, Kellymom is a great resource for pumping info & tips, and for going back to work concerns in general, as is this website, also if you have not gotten a copy of The Womanly Art of Breastfeeding (8th edition) I strongly suggest it, it has everything you ever wanted to know about breastfeeding in general plus two chapters dedicated only to going back to work/separation from baby and pumping.
Does baby ‘need’ to be burped? He may, and that is fine, but many breastfed babies don’t. And some babies prefer one side ‘at a time’, others always nurse on both breasts every feeding, some go back and forth a few times, and most do some combination. It’s all normal. Just keep nursing whenever baby or you want to, for as long as baby and you want to, on whatever side or combination of sides you and baby want to. I don’t think you need to worry about when baby is actively swallowing and when baby is “comfort” nursing, that kind of differentiation is only needed when a (usually much younger) baby is not gaining weight. Also don’t worry about how long it has been since baby last nursed, its fine to nurse more frequently than every 2.5 hours if baby wants (babies usually tend to want to cluster nurse-nurse very frequently part of the time and then take a longer stretch between nursing here and there. This also can make what are actually two or more nursing sessions seem to blend into one very long one.) At La Leche League, we try to ask how many times per day baby is nursing, (normal would be about 10 times OR MORE (sometimes much more) per 24 hours.) When people say baby is nursing every 2 or 3 or whatever hours, I wonder if someone told them to feed baby every 2, 3 or whatever hours. Babies are not born with wristwatches on, and usually (there are exceptions) babies do not nurse in any kind of regular every such and such hours pattern. Slowly, slowly, overtime, babies get more efficient at nursing & tummy grows and holds more and nursing sessions tend to get shorter overall and less frequent, and even more regular. But it is not a steady one way street, because due to growth spurts, developmental progression, illness, upsets, and for mysterious reasons only babies know, baby will increase time at the breast here and here. And nursing babies & children of all ages still at times want to ‘comfort’ nurse, nurse for a long time, fall asleep at the breast, and/or keep nursing while asleep. It’s all normal and good.