I’m very new to using OpK on my 2nd month

My period ended fully i would say Friday and Saturday and Sunday spotting

Today i took an opk and it looked like this.

I did drink a glass of tea before taking a 30min to a hr before .... i felt i had to go so i grabbed a test to see and ended up with this kind of result because i think that’s what happened last month i thought i had a surge but apparently not because i didn’t get pregnant

I’m new to this i shouldn’t drink anything at all before i test ? Like wait until i feel the need to

Go? And never FMU correct ?

So this is pretty much false ?