Breathlessness And Sharp Pain In The Left Side By The Heart

Hello , need help please . My wife is 30yrs old . For the past year she has noticed her self not being able to catch her breath from time to time. She easily gets fatigue . Just last week she was having a harder time catching her breath. She went to the dr and they ran a blood test . She didn't understand what they were telling her but they said something about her blood cells are enlarged. The set her a appointment for another 2 weeks to talk about it. Well the next day after she did the blood test she caught I think walking pneumonia . We went to the family DR and they only did a X-RAY and said to take some Antibiotics . It's been about 4-5 days since she's been on Antibiotics and her cough is slowly clearing but she still cannot catch her breath. She noticed also tingling in her left arm and the fatigue is still there. Also she gets very bad night sweats. We have a appointment in 5 days but I'm scared she can get worst by then . We are scared to go to the hospital because there are so many viruses and it seems when they keep you there you always get admitted in and get even worst :( . Need help . We have 2 young boys and we are very worried . What do you think she is sick with ??? Help. Thank you .