J.G.
Even if you "dropped" that doesn't mean labor will start soon. My last was my big boy - he did "drop" early. But it was only because he needed room to move. I felt like he was sitting on my lap for over a month, then the last few week I couldn't sit with my legs together cause my tummy won't let me. Yes, I felt like he was going to fall out and I had to pee all the time. I wore light pads just incase - sometimes toward the end he would kick my bladder and I just couldn't help but leak. So, the pads help me from anyone else knowing & made it easier on me when I was working. The bathroom can be so far away when you are at this stage - even if it's only 3 steps away.
Never feel like an idiot when it comes to anything dealing with your pregancy... I'm having #5 in July. And I still ask questions... I should be a pro at this by now, but all of them are different & the saying "once you hold the baby all the bad stuff dealing with pregnacy goes away" is so TRUE!
The back issue could be the way the baby is laying... sometimes they lay on nerves or push against them wrong. I had to ask the doctor why I didn't have feeling in my privet area... for days. Just so happened the doc rubbed my belly really hard and the baby moved and the feeling was back. It was kinda like sleeping on an arm wrong & waking up with your arm asleep. You doc should be able to give you some more insite into that.
Just remember - you are on the home streach... you'll be holding you littlest love soon. Congratz!!!