Easy bruising , low white cell count

Thanks to anyone who has any insights.
Our 12 year-old son has a medical history that is starting to conern me.

At age 9 he was hospitalized with Salmonella and several months later he had pneumonia. The infectious disease specialist we saw at the time said these were unrelated.
At age 10, we noticed actually what I thought were some time of big bug bits his Dr. said they were bruises. Referred to hematologist who said he does bruise easily and to let the Dr. know should he need surgrery. He gets big bruise from straddling raft in a pool, or a bruise from dog jmping on him. From things I would not think would cause bruising.

Last year, at age 11 he had a several month period where he was very fatigued. Falling asleep in car going place, taking nap after school which he had never done before, falling asleep on couch before school. Dr did rule out mono. He has improved on this, but sometimes still has similar symptoms.

He was recently ill with 103 degree fever, cough with chest pain, fatigue, nausea, abdonimal pain, body pain. This lasted for 4 days and stared his first day back at school after Summer. His Dr. did note that he does tend to get illness like this several times per year with high fevers.

Our son's chest xray was clear, no strep. CBC reveals low white count. That's all Dr. said..I do not know how low. She wanted CBC redone and we are awaiting results. I just thought she wanted to make sure the virus or whatever he had is gone.

Last several months our son has also developed a skin thing with pink and red raised bumps on the back of his upper arms and cheeks on his face. I thought it was eczema. Dr. says no. She says the bumps are fat filled and to use a loofah or exfoliator. This has helped a bit on his face, but not on arms.

Frankly, I was not concerned until this week started thinking about his entire medical history and now I am wondering if Dr. is trying to rule out something serious or unusual.

Just wondering if anyone would be concerned and perhaps see some type of specialist to pull everything together..or perhaps I am just being neurotic as we only have one child!!

Thanks for any feedback..and my prayers to anyone who has or has a loved one that is posting here that has cancer...!