Abnormal cells for 3rd time. Previously treated CIN3

Hi, 

I had the results of my recent smear on Thursday and abnormal cells again.

I had laser treatment for CIN1 in 2011 and a Lletz for CIN3 and Hpv present in 2014. 

My following smear  was normal and no HPV detected so I was told I was ok to go back to 3 yearly testing. 

I've sinced moved and had my recent smear done 2 weeks ago at a different Dr's. When I went through my history the nurse seemed really shocked that I was put back to 3 yearly testing after just one clear result. 

I'm really worried that a mistake was made and I should have been tested sooner. The letter just says abnormal cells detected and referred to the medical specialist group (I now live in the Channel Islands so things are slightly different to the NHS) I'm awaiting the appointment letter for them.

I'm scared the CIN3 returned and has advanced to Cervical cancer.

Also does anyone know what treatment is likely to be recommended reoccuring abnormalities as I've already had a Lletz. 

Thanks