Period late

It’s been almost 2 months since my last period, I’m usually irregular but never this much. I’ve taken 2 tests both with lines that faded away, and showed up hours later. I know they could be dye runs or evap lines I’ve just taken many of these tests and never had them be like this before. I’ve had cramping nearly every day but no signs of blood. I’m wondering if I’m not pregnant what could be causing me to be this late?