Last March I noticed a pain at the bottom of my tail bone

Hi everyone.. Im am a 15 year old female.. Last March i noticed a pain at the bottom of my tail bone and thought nothing of it.. It was sore to sit down.. My bowel movements felt hard and sometimes diarrhea follwed by blood.. It all was fine for a few weeks and then the pain was back... My stools haven't been very regular since.. either a funny colour, hard to pass, small, thin and mostly diarrhea.. A few months ago i got a pain in my tummy and everytime i ate i felt like i just wanted to be sick or pass diarhea.. That happened for a few weeks.. I can feel lumps inside my anus and one outside my anus.. I am now passing more bowel movements each day and are very little at a time and really watery.. sometimes followed my bright red blood which when i think about it is coming from these lumps.. I do know bowel cancer runs in my family.. My granda had it and some of my great uncles.. I do know my mum suffered with polyps and so did my aunty.. But they have been removed with a colonscopy. Please cna you help i am really worried and i just wish i could pass normal bowel movements.. My bowels never feel empty! what could it be.. Thanks so much for taking time to read this and help me!! x