The small painless swellings on either side of the neck are most probably enlarged lymph nodes. Lymph nodes usually enlarge due to infection of the draining area. Those in the neck are enlarged if there is an infection in the throat (e.g., streptococcal tonsillitis), skin of the face, or the skin behind the ear or scalp. Neck lymph nodes may be enlarged as a result of a small and apparently insignificant skin lesion due to primary tuberculosis. The investigations done so far do not show any evidence of tuberculosis. Please get the child examined by an ENT specialist if the swellings persist or enlarge despite antibiotic therapy.
Constipation at this age is often secondary to poor eating habits rather than hypothyroidism. The thyroid function tests show normal T3 and T4 even though the TSH levels are the upper limits of normal. It will be prudent to repeat the tests, if conventional simple remedies fail and the growth of the child is affected.