Monostructural activities (single modality workouts) are important to your training and should not be skipped over. The purpose is primarliy to improve your cardiorespiratory capacity and stamina. These are typically long, slow, distance efforts that don't elicit that super high intensity that we're used to. So do this...and do the best you can.
What's your 2k PR? Set your pace at about 10 sec slower than that (your 500m pace for the 2k) and just sit back and relax.