Hi, I'm new and I really need some help/advice please

Hi, I'm 16 and I have bumps on my neck, that have been there about a year now. I've been to the doctor and gone to fast track at my my hospital. My mother and grandmother think it's nothing, just a bump. The doctor at fast track had me get blood work done and they haven't called back about anything yet. The doctor at fast track also told me it could just be swollen lymph nodes, or possibly lymphoma, but she doubted I had cancer. Well, its been months now, and I'm not sure what to do. My mom doesn't want to take me to the fast track anymore because she doesn't think it's a big concern. I've read a lot on this site and other sites, and by the looks of it, I believe the doctor, and it's I think it's possible I have lymphoma. I hope it's not, but I'm not sure what to do. should I go to the doctor again? I just don't want them to brush me off again. I really want to know what it is, but they don't find it too concerning I guess, but I'm scared. I've read a lot about lymphoma and i just don't know what to do or what to tell the doctors. Please help me..