Scared of stomache cancer, drs arnt taking it serious

Hi everyone I'm after some advice on how to be screened/tested for stomache and bowel cancer im worrying myself sick amd feel pretty defeated by the drs :( 

For a year ive had bad stomache pains, lightheadedness, heartburn and recurring sessasion of a lump in my throat. The lump sensation they constantly put down to larengytis and give me antibiotics. Ive recently started to have awful pelvix pain in my ovaries and bleeding after sex wich has sent me into pannic mode i have cancer and its spreading, mr dr inst concerned due to only being 27.

Ive sent off numerous poo samples wich come back with blood and mucos so they suspect a bowl desease yet no further tests, my drs shut down and my new drs seem fed up with me, my bloods aleays come back with high lympholites but all they do is re test in 6 weeks. My last appointment i had a cervical exam she said it seemed ok and took swabs and is refering me for a internal ovarie scan but could take up to 12 weeks. And again i had the usual blood tests with a follow up app next week.

This week im short of breath and im not sure if its due to worry or if its a cold but i am so fed up of feeling scared and my drs just thinking im nuts, she last gave me ompoznole for the nausea. I have 2 young boys and even looking after them is getting hard with ny dizzyness and the pain. 

What do i do tho? Imngoing through drs like no tomorrow i can not afford private my stomache pains wake me up in the night and constantly feels cold inside. If my breathing doesnt improve today ill try get an appointment tomorrow, i just want to shake them and say help me!