Tightness And Cold Sensation In Chest, Tender Breasts With Fluid Secretion. What Could This Be And Treatment?

I am 34, weight 68 kgs, female. At the moment I have what I believe to be a chest infection - I guess tight chest, but feels very cold inside my chest with each breath I take, feels like phlegm is "stuck". I also have very tender breasts, they were secreting fluid last week, not pregnant, although not as sore as last week admittedly. Any simple things I should be doing to relieve this? Had for approx 6 weeks now, the sinus infection has mostly cleared up now too, but incredibly annoying, I am self employed in sports therapy - I cant even run for a bus right now, so showing clients exercises is rather difficult