Yeah, that's tough. You're trying so hard to start new habits and then this happens. I would say, 1. Take care of yourself and get some rest when you are sick (don't exercise). 2. Being sick isn't an excuse to eat a bunch of off plan comfort foods. Keep the proper nutrition going. Your body needs it more now than ever. 3. GET BACK TO EXERCISE WHEN YOU FEEL BETTER! I put that in caps because that's the part that always seems to get me. A week on the couch and then bammo - I'm completely off plan again.
I think keeping the plan going though, with your eating will help. Then, when you start back up with exercise, give yourself a few workouts that are a little milder. Don't get discouraged if you can't just immediately jump into your previous level.
Reminder - this is a lifestyle, not a temporary thing. We get sick. It happens. Use it as a way to get sick like your new thinner self would and not like your old self.
I hope you feel better soon!!