In some cases, increased BP can be reduced by TRT.
Wikipedia: "Creatinine (from the Greek kreas, flesh) is a break-down product of creatine phosphate in muscle, and is usually produced at a fairly constant rate by the body (depending on muscle mass)."
Problems with the kidney's can change levels. TRT will not harm healthy kidneys and might not have an adverse effect on unhealthy kidneys.
If with the T you have worked your muscles to a high degree of soreness, this can increase levels of creatinine as well as some other markers. Trauma or muscle bruising can do this as well.
"Creatinine can also increase temporarily as a result of muscle injury."
Taking creatine can increase creatinine.
Creatinine levels in healthy individuals vary with % muscle mass - hence males have higher levels than females.
You also need to be looking for indications of a possible kidney problem.