I'm two months late on my period. Today I felt this sharp pain in my lower stomach area to my groin area. Now it hasn't gone away. I did take a pregnancy test it was negative I took it about 3 weeks ago?

You need to be seen. Left sided abdominal pain can be multiple things and is difficult to distinguish without a physical exam and an imaging study such as an Ultrasound. You should go to your local doctor or an urgent care to determine the cause of the pain. .
I would consider. pregnancy test at least 1 week after your late period, if your period never came. The longer you wait the more sensitive the pregnancy test becomes. If you start having a regular period then it's unlikely that you are pregnant. Pain in the groin area may be related to pregnancy or maybe infection of the ovarian tubes or bladder. Go get yourself checked by healthcare provider.