Diagnosed With Walking Pneumonia. Having Fever. What Should I Do?

Question : My 5 yr. old son has had a fever since November 15. The fever started at 102.6 and went up to 104.4. I took him to the children's ER on the 17 and was told to give him asthma medication because he was crackling. He was diagnosed with walking pneumonia on November 19.(He had a chest x-ray the day before 11/18 and it came back clean, only to be seen in the ER the next night with a fever of 103 and I told that he has walking pneumonia at that time). He was given antibiotics to take for 10 days which he has finished. He saw the pediatrician on the 25th and she said that he sounds all clear. His fever was still going up and down at that time and that was day 6 of being on antibiotics. He is still getting fevers of 101.5 that come and go. Can you please help as to try an give me some information as to what is going on with my child.

How do I get these doctors to draw blood? I told his pediatrician that the fever keeps coming and going and she seems to think this is ok. He was seen in the ER three different times and did they draw blood on any of these visits. My child is not a kid that gets fevers like this.