I gained 12 pounds from Wednesday to Monday. It's swelling but I also have gestational hypertension. My Dr is also checking my urine weekly for preeclampsia. I am 35 weeks now and as long as gestational hypertension don't turn into preeclampsia and my BP meds continue to work I will be induced at 37 weeks.
Yes, swelling will show as weight gain.
Was your blood pressure ok? Swelling and protein in the urine is not good but only a concern if your blood pressure is high too, as it can be a sign of pre-eclampsia. Drink plenty of water to try get the swelling down and keep your feet and legs elevated to hip level when you can, with support such as a pillow under your knees.
I gained 7lbs in 2 weeks. My Dr said that it happens when the baby packs on weight. I haven't gained anything else since the 7lbs. I actually lost a lb. I'm 38 weeks and 2 days. Also protein can be caused from losing your mucus plug. Or at least that's what my Dr told me.