How do I know if it's allergies or asthma

[csun]

At about 10 months, my previously very healthy son, came down with what seemed to be a bad cold. I tried to handle it at home with vaporizers and other home remedies. Finally after a week, I took him to the doctor. The doctor prescribed Claritin. Two weeks later, my son’s symptoms were worse. He was coughing all of the time, his chest rattled when he breathed, and his nose was always running with dark green mucus. I took him back to the doctor and he said that it was a sinus infection and gave him an antibiotic. After the antibiotic was done, my son had not improved at all and I took him back to the doctor who then gave him a stronger antibiotic. 3 days into the new antibiotic and my son developed a high fever of 103 degrees. The doctor then told me that even though he was on the antibiotic, he had developed an ear infection. Now we discontinued the current antibiotic and began a four day round of antibiotic shots. When this did not help, we were sent to have his sinuses x-rayed. The x-ray revealed that 3 of his cavities were 100% blocked and 1 was 50% blocked. A culture of his sinuses told us that the bacteria were antibiotic resistant. My doctor told us we could take him home and try to ride it out, or put him in the hospital. We chose to take him home. That was 2 months ago. Sense then, my son has had croup and the flu all in one week, and continues to cough every morning when he wakes up and most of the day he has a terrible loud rattling in his chest, and constantly has a runny nose which is think and dark in color. My doctor has changed his allergy prescriptions to Allegra and a Flonase spray. That was 2 weeks ago and nothing has changed. I’m at a loss and I don’t know what to do. My family has a long genetic history of asthma; I even had asthma as a child, but have not had an attack since I was about 10. My husband has had terrible allergies since he was a young child. Also, my sons tear ducts are blocked. He has surgery in a couple of days. My pediatrician seems to think that this will make a huge difference in his ability to drain the bacteria and allergens he comes in contact with. He thinks it will have a dramatic impact on his health. The ophthalmologist who is doing the surgery doesn’t think it will impact his health all that much. He does not think that his blocked tear ducts would cause all of the sinus problems or breathing problems that he is having. At this point, I don’t know who is right. I’m just not sure how long we should continue to give my son allergy medicine that doesn’t seem to help. My doctor said that an Allergy Specialist won’t see him because he is only 13 months old. I want to know how to tell if this is just allergies or something worse. Could it be asthma, and how do we find out?