Anna:
Please feel totally OK to NOT work out for a few days. Let your body recover its strength or you will be giving to the workout the energy and resources you need to recuperate. Cathe is the toughest there is, give yourself a break! With litttle kids in the house who rely on their Mum always being there and not taking to her bed, I would listen to your body and let it rest when it needs to.
It's not a question of not "letting a cold stop you from working out", that's too gung-ho for a sick body, in my opinion. With a cold, your body is trying to tell you something: what do you think the message is?
Clare