first time using OPKs

Kate • DS born 4/30/14 ~°~°~°~ DS#2 arriving April 21st!!

first a little background, I have longer than average cycles(38 days) I started testing on cycle day 4 (AF ended on day 3) I am trying a store brand opk from cvs and all three tests look like my LH surge is happening now, is it just the test or can I be ovulating this early?