swelling after work-outs

In the past couple weeks my energy has really gone down... my jogs have turned to mostly walking... but I am still getting 30 minutes to an hour of exercise everyday, and still using my weights and stepper as well.  I feel better when I do something to keep active, but my body doesn't seem to be agreeing with me... after just a 30 minute walk at the park today my hands and feet looked like balloons... is this a sign I need to stop, or is this just normal at this point in pregnancy... Would really appreciate any input...thanks.