Clear blue digital test

Lucy
Has anyone used a clear blue digital test and it was wrong in how many week you were? AF last arrived 7/7 and I took a normal test positive and digital test on 13/08 the other test can back 3+ weeks then instructions say add 2 weeks which is fine with me but I since my coil was removed my cycles have been all over the place meaning ovulation has been different too. I have my 12wk scan in 3 weeks but thought I'd ask the question x