should i be eating my exercise calories??

Hi Guys, new to MFP and i am wondering if i should be eating my exercise calories. I am on 1200 cals a day and currently have not been eating my fitness cals.. I have had quite a few days where my net calories were between 200 and 400 cals due to lots of walking.. am i hurting my weight loss if i dont eat them ( ie starvation mode) or hurting if i do ( ie eating too much) i might say i am not hungry at all with 1200 cals per day.