I Have A Golf Ball Size Lump At The Base

I have a golf ball size lump at the base of my sternum it is discomfort when touched but no real pain it is hard and doesn't move I also have been sick for two months mainly headaches Nasal congestion and starting to move into lungs I had a scope and biopsy of stomache months ago they found a bacteria and placed me on antibiotics I have taken over 20 days of amoxicillin I had a throat culture and it grew some sort of bacteria doc didn't know what it was. I also have been having blood after I take a poop. But only when I wipe