My poly morphs count is 28% only. Is it mean that i had low immunity?

By poly morphs, I think you may be refering to polynucleated white blood cells or "segs". They should be the majority of the white cells, the second being lymph cells. I wonder if you mean immature white cells which appear in low numbers;ie 2 %. I need to see your entire report to understand what the results may indicate. If you had blood work done, why didn't you discuss the results with the doctor who ordered it?