Colonscopy

Hi All
I am just wondering i have been having tummy pain since July. I have had 3 ultrasounds , mri and ct scan. So far they have found a 6cm fibroid and some cysts on my left kidney. But they don't think that's causing the pain. The gastronologist wants me to have a endoscopy and colonscopy and I am really scared it's something serious. My bloods are all ok they even checked the tumor markers. Anyone with some advice or that has been through something like this please let me know. Thank you