13 yo son w extreme fatigue, overweight, chills, joint pain etc. Cbc showed wbc 11.8, abso neutro 7.1, abso lymph 3.6, and abso mono 0.9. Also TSH 7.250. I'm worried about leukemia. No other signs of inf at time of blood draw. Shld this b concerning?

Leukemia! why should it be? your son's doctor is doing a good job, pertinent labs were ordered, and results are fine, may be TSH is on the higher side, but it can be followed, and hypothyroidism could be the problem and can manifest this way, however, clinical judgement is important, trust your doctor, your son will be fine, wish you all the best.