What Causes Lower Stomach Pain,headache And Dull Pressure Behind The Nose?

i am a 19 year old girl, i havent made any drastic lifestyle changes and for the past few weeks ive been getting stomachs aches in my lower abdomen every day, i also feel weak and shakey sometimes, i often feel that i have no energy even though im eating properly and getting lots of rest, ive been getting hot flashes every now and then for the past few years, i dont know if this is releted but i get head aches quite frquently that are right at the front of my forehead, and it feels like theres a dull pressure behind my nose (the pressure and head aches always come together) and it feels like im always sniffling, do you think theres anything wrong with me? thank you