Ovulation tests

Sarah

I did a digital clear blue ovulation test 4 days ago and it showed I was having a surge. All of the test strip ones I have done never showed a second line which was dark

Then I did one today because the test strip one I did actually had a darker second line or darker than usual anyway. The digital showed I was having a surge again.

So the first one was positive 4 days ago and now another today... Is this normal?