Stomach Ache

I need advice. A couple of weeks ago I started getting intense headaches in the evenings. They were extremely bad but I wouldn't call them migraines. A week and a half ago I started getting stomach aches. They were like someone was twisting my internal organs all the way from the front to the back. I also can't sleep. Not sure if it's just because the stomach aches are always there. For the past week, i've had maybe 3 hours of sleep a night. Going to the doctor on monday but just wondering if anyone knew what this was about. Thank you for your input.