UPDATE: I have a swollen lymph node on the other side of my neck now. The chest pains have gotten worse however. Starting to think they might be a bad infection 

Hi, I'm a 22 year old female and I'm scared to death that I have Cancer (HL in particular). 
i want to also say though that I have severe health anxiety and so I'm hoping to god that it's just that but this time I'm not so sure. 
It all started a couple weeks ago with pain in my right breast that felt like a burning sensation and a stabbing pain. There's no lumps as far as I could tell but minor swelling. I came on my period a week after this so I thought oh it's just normal breast pain. However, recently got worse and I felt very unwell. My symptoms are as follows.  breast pain, breastbone feels bruised, chest pain, armpit pain on one side, shoulder and back pain on one side and ear pain on one side. As of 3 days ago I developed a fever and a cough and yesterday I noticed a lump on my neck. I went to the doctors and he diagnosed me with strep throat/ tonsillitis. 
But I've had tonsillitis many times before and this is different. 
the lump on my neck isn't hard but isn't soft either it has an almost orbeez like texture and it moves a little bit much not freely.  It isn't painful to touch and it appeared overnight after my cough started.  
 

can someone help me I feel like I'm going crazy because everyone around me is telling me I'm just being silly