Hi everyone. I am 24 years old and have been having issues for about 3 months now (although looking back it definitely could've been longer). 
My main issues are bloating, incessant stomach gurgling, gas (burping and farting a ridiculous amount) a lump in throat feeling and having to clear my throat all the time especially after eating due to mucus. Have had looser stools/diarrhoea on and off with mucus in stool but never pain with it. Have had pain under the ribs in stomach area though occasionally. My GP said "probably IBS and reflux" and gave me Omeprazole but it hasn't done anything.

I'm super scared that it's colorectal cancer or stomach cancer. My GP will not refer me for a colonoscopy because so far I've had no rectal bleeding. I've read a lot of stories from people my age who had similar symptoms and were very sick (stage 3-4 when diagnosed) so I am absolutely panicking. To make matters worse they know I have a family history of it (grandfather and possibly grandmother) so I'm worried it could be genetic.

They're doing some stool samples but that's kind of the limit to their investigations.

Any advice would be great. Just really quite anxious