I done a urine sample test and it come up that i had blood in it , i feel ok so am scared why that's showing?

Why urine sample?: What was the urine done for? Any particular symptoms or just routine? It sounds like you had microscopic hematuria. If you did not have this before, then it is not your baseline in which case given your age you need a workup to figure out where the source of blood is. It could be polyps in the bladder, a UTI, an STD, possible malignant growth in the urinary system, etc.