I am sorry you are having trouble with your kidneys. It sounds like you have nephrotic syndrome which is how my lupus was discovered. A kidney biopsy sounds scary (I was terrified!) but believe me when I say it is no big deal. The procedure is easy and painless but it is important for them to find out what class, or type of kidney disease you have. You are losing alot of protein through your kidneys and this constant protein loss will permanently damage your kidneys and cause loss of function if it is left untreated. The good news is that with the right medication it can be easily treated. I remember the days when I had rolls in my ankles from all the fluid build up, but I have been fluid free for several years now. It is good you are seeing a nephrologist and the meds he has you on now appear to be helping as shown by improved labs.
I also can feel my heart beating at times but I have problems with my potassium levels so I think that is the cause. In your case I would have it checked out right away. Hang in there and feel free to vent anytime. I know how scary all this can be, but it is treatable.
DX: Kidney Disease, (? Lupus Nephritis) 2002
DX: Raynaud's Phenomenon and Lupus (SLE & Class V Lupus Nephritis) 2005
DX: Anorexia and Hypokalemia 2006
meds: plaquenil, amiloride, klor-con, lovastatin, allorpurinol