What Could Be Causing Severe Shortness Of Breath, Difficulty Sleeping And Eating, In A Long-term Smoker?

I'm 61 yrs old. The past 2 weeks I've had trouble breathing, sleeping and eating. Now I feel worse today. I can't hardly breathe. I'm very scared. I've been a smoker for 45 yrs. I cut down to 5 cigarettes a day. I took my blood pressure. It's 101/58. What can be wrong?