J.O.
I was sick (constant nausea with vomiting 3 to 5 times a day) at the beginning of both my pregnancies -- although this one lasted a lot longer. I tried all there was to try: Sea Bands, ginger, B6, even the meds were hit or miss. So I completely understand the 'functioning' part, especially when you have another child in the mix. The only thing that I found to really help was acupuncture -- after the 1st treatment, I went a week with only minimal sickness; after the 2nd treatment, I was only sick once in a week; and now I'm going on 2 weeks sickness free!
The pain you're talking about I have also. From what I understand, it's just the ligaments and muscles stretching. We are feeling the pain sooner because it's not the 1st pregnancy. But I would go ahead and mention it to your doctor just to have it on record.
As far as boy vs girl, we don't know yet. But I have friends that had completely different pregnancies and had the opposite gender as the first; and I have friends who had completely different pregnancies and had the same gender. In our case, most of the same things are happening with a few differences and my doc 'thinks' girl this time (we had a boy the first time).
Congrats on your pregnancy!! Here's hoping the sickness leaves you soon!