Help!! Slightly long post! Sorry!!

My last period was Feb 17. I bought an OPK last cycle and didn't use the whole box.. so I started testing with that same box on Feb 21st. I had negatives until Feb 26 is when and used the last test in that box last night (Feb 28)....

Bought a new box last night and used the first one this morning with the stick it came with and the one I've been using since my last period.

I put one test in the new stick and went to take the cap off and the whole test kept coming out (didn't do this with my other box). Finally got the cap off and take the test and it's negative/low... How??? I just took the other one and it was HIGH?!?! So I grab my old stick and put a new box test in and the same thing with the cap happens.. take the test and it says PEAK!!! Sounds about right considering the highs I got the few days before... So I decide to take a new test in the new stick and again I get s negative/low.

Is it that normal with a new test or did I just get a bad box? What do I do if I got a bad box???

*Top test was from the new stick - said negative/low

*Middle test is the new stick - negative/low

*Bottom is old stick with new box test - PEAK