52 y/o female with chest pain, geting worse over past several days.

Hi ...

I know this is going to sound SO stupid , I am an intelligent woman ...a nurse in fact but I am terrified !! I have had pain in my chest worsening over the past week. It is a dull aching pain and now has moved to not only my heart but between my shoulderblades. I do not have tachycardia , but more of a feeling like my heart skips a beat every now and then. Sometimes I am afraid it is going to stop and not start again. 

The stupid part is I am so scared that I will be out of work which I cannot afford to do since I do not have sick time that I am paralized from going to the hospital. I have an appt with a cardiologist on the 20th but am afraid I won't make it till then.  I keep wishing this will go away but its not. I am also VERY tired and short of breath upon exertion. This pain seems much worse in the evening when I am tired but it is 'there' all the time. It is not bad enough that it keeps me awake and up until today when I wake in the morning it is very faint.  I am not overweight but I have smoked all of my life. I am post menopausal and also have had a battle with lyme disease that was undiagnosed for many years.

I don't really know what my question is ? The pain feels like a dull burning , I guess I would like to know your opinions on what you think this could be ? Thanks for taking the time ...Kat