Breathless and in pain

Patient: Hello. I have been suffering with chest pains on and off for a few weeks, mostly at night. Over the weekend i developed a very tight chest which was very painful when i breathe and palpitations. I went to see my GP who said my chest was clear of infection but could hear sounds that lead him to believe it was to do with my asthma so prescribed me steroid tablets. I took the first dose on Monday and again Tuesday but felt no better. By Tuesday afternoon i could hardly speak in sentences i was so short of breath. GP checked me again and said chest was clear. Nurse gave me a nebuliser which helped initially and calmed my rapid breathing. Wednesday i was still feeling palpitations, heavy feeling on my chest and back pain and just feel like i am trying to breathe through water. I went to see my GP again who said my chest is clear and to continue with the steroids. I would like to know if there is anything else this could be because i feel no relief from the steroids and am still very uncomfortable. Thank you

Symptoms: tight chest, short of breath on and off – not constant, heart palpitations, upper back pain, dizziness ( although i do have vertigo)