Lumps on body, sore one on rib?

right, so i have a realy sore lump just underneath my bra line and it keeps getting bigger. its not a spot but it feels quite deep and is realy uncomfortable. it bled once but now is just painfull. Ive had similer smaller lumps allong my beltline, armpits and knees. doctor said that the armpit one was just a swollen lympth gland, but i dotn think you have them on your ribs? im only 16 so its not that cool :/ dont realy know what to do. any ideas on what they may be and how it can be helped?