False Positive HPT during LH surge?

I have been using OPKs (Easy@home) throughout my cycle, and today I got a very clear positive. For the heck of it, I also dipped a HPT (easy@home) in the same urine. It was a faint positive! I tried another- same result. In a hurry, I ran to the store and got a FRER. It was a stark negative. Has anyone else had a positive HPT during their LH surge? I mean, I'm sure most people would not be testing for both like I did, but I am curious since you are not supposed to ever have a false positive HPT.