Just wondering if anyone can help or been in a similar situation?

I had a mammogram a few months ago which was clear. I found a hard lump in my breast but because mammogram was ok I put it down to peri menopause. After being ill with stomach issues, weight loss and 2 UTIs I had FBC and stools taken all which were clear. I was still not feeling great and was back at the Dr twice. Out of the blue Dr asked if I had any changes in my breast but they could see my last mammogram was clear. I told him I’d a small lump but put it down to age/hormones. He arranged for me to see a female Dr who felt a lump but not where I had found it. I was also referred for a CT scan which I had last week. They have found enlarged lymph nodes in my chest so I’ve been referred to respiratory. They said it could be lymphoma or sarcoidosis (which I had chest X-rays for in May due to joint pain which they had originally thought was rheumatoid arthritis but chest showed clear so it was ruled out and put down to wear and tear.) 

Could the lump in my breast be related to the enlarged lymph nodes and not be related to breast cancer? I mentioned this to my Dr (who originally had to consult with a more senior Dr) and he said he didn’t know. I’m now anxious that I will have breast cancer and lymphoma. I’ve had a pain in my left chest and shoulder on and off for days and I think it’s from anxiety but of course I’m overthinking everything right now. I’m trying to remain positive as mammogram and blood count were all ok. 

Sorry for such a long post. Just really looking for some advice. 

Thank you