I recently got blood work done and my bun was 29. blood creatinine was 1.25. the day i had it drawn i had worked out a few hours before. ?

Not likely: Depending on your ethnicity and muscle mass, these numbers could represent a decreased kidney function between about 70-80% of normal, and you should have the lab repeated, and possibly be seen by a nephrologist to see if there are other (often reversible or treatable) causes of these tests, which are unlikely to be solely the result of a "workout.".