Purely out of preventive reasons I did a blood test on creatinine levels. I got results - 109 umol/l (the range is 74 - 110). Is this concerning?

No. All laboratory results need to be interpreted in the clinical context and the doctor who ordered the tests is usually in the best position to do that. Having said that, your creatinine is within normal limits. If you are a muscular person there would be even less cause for concern.