Ouch

I just started going to the gym again. I decided I would try some of the equipment they have since this gym is more into toning up then the cardio aspect. I tried an ab machine on Monday. I made sure I was using it correctly. Yesterday I was pretty tender and again so today.I just returned from the gym where I tried the same machine again. My abs said no way and I couldn't successfully complete a full rep. My question: do i work through the pain and discomfort or do I let the muscles rest a bit more and gradually get back to the machine over the next few days? I am trying to get to the gym MWF. Also just so it's known I've never really WORKED my abs just keep a solid core during other exercise (obviously not very well! Lol. )