10 year old son got tripped while playing football. Fell on chest. Coughed up mucus right after. Wheezing and hard to breathe at first. School nurse said O2 level was at 94 and at first couldnt hear air in lower lungs and wheezing. After a 1/2 hr air movement could be heard in lower lungs and still some wheezing in upper. The noisy breathing has stopped. He is complaining about his chest hurting and feels like its hard to breathe. He does suffer from cold air induced asthma. Should i nust continue to monitor at home? He is moving around like normal.