What Causes Severe Pain In Armpits And Breathlessness?

Hi l have been feeling really unwell for the past three to four months. Seem to pick up infections very easily. I have very sore red rashes on my chest shoulders and face and forehead. More recently l have felt breathless without exserting myself and l have severe pain when l press a couple of inch from my armpits.Cuts and sots on my face take along time to heal over in most cases its skin growing over the spots rather than the spots healing. My face and and chest are a mess very noticeable. Doctor gave me antibiotics and antibiotics cream for my face but they are not easing the rash more concerning is the on set of the pain under my arms and breathlessness. And l don, t feel right l am concerned l am in the progression of feeling unwell lathargic. I do smoke and l am 49 year old. Can you suggest what maybe happening and recommend what if anything l should do next.Thank you in advance for your assistance on this matter.Regards John