😭😭 Advise??

So I finally started feeling baby kick, I’m 16w5d, and baby has been kicking me in the lower abdomen , but right after I get this really bad pain in my upper abdomen , not sure if anyone else has had this happen or what, I have an appointment with my OB tomorrow but wasn’t sure if anyone had any advise, so far baby will only move/kick when I sit down to go pee, otherwise I don’t feel anything... 😔 not sure what to feel or think kinda nervous but as I said I do have an appointment tomorrow .