Creatinine 1.3 is it bad?

Maybe (not) . . .: It depends. Don't you hate those answers? Creatinine is only a partial assessment of your kidney function. For complete interpretation, we also need your gender (female in your case, i presume), age, ethnicity & body weight. These values are then incorporated into the egfr which is a better measure of your kidney function. Most labs automatically calculate this so ask for result. Normal is 90-100+.

Depends: Nowaday's "normals" are calculated for sedentary people. Creatinine in health is a function of muscularity. When i've been lifting a lot, i run 1.4 or even 1.5 in my glory days. The fad of estimating GFR from a spot creatinine is considered subscientific by many pathologists & nephrologists -- what's the use. If a skinny girl has creatinine 1.3, i'd worry about her kidneys.