Hi Julie

its perfectly understandable that you feel anxious. Feelings of anxiety about anything are not easy to manage. What do you usually do if you feel anxious? Have you tried it? Talking often helps and I guess that's why you posted. Have you got people to talk to? It's better out than in. What do you do with your worries? Do you share them? 
Your cancer was caught early so you were lucky. That's great and you're being screened to see if you've remained free. Two good things already Always good to get the facts then you can decide on action. I hope you managed to get some sleep