Ditto what Shell said!
It can often be referred to as Pitting Oedema (i think) - which is pretty much all the swelling and then when you push on them the dint stays there for a while. I had it too and stressed out because it came on quickly, but i got my bp & urine checked and everything was a-ok.
Keep your feet up - above the heart line and the swelling should come down, and drinking more fluids - water (ironic i know), will also help.