If your fasting glucose is 99 and your a1c is 5.9is that considered pre-diabetes?

No: But you're right on the edge of pre-diabetes. For now, that's good but be mindful of your diet and exercise though.

Need more tests: An a1c of 5.7-6.4 is in the prediabetes range according to american diabetes association guidelines and aace since 2010. However you need 2 positive tests to give you a diagnosis. Another a1c > 5.6 or fasting glucose 100-125. It is time to put together a healthy diet and exercise routine.

Yes: An a1c of 5.9% is indicative of pre-diabetes per ada criteria. If your fasting glucose is 99, it could be over 100 if you repeat it again in the future. At this level, you can prevent progression to diabetes by keeping your weight normal and increasing activity level.

Yes, but: The hba1c is within range for pre-diabetes, fasting sugar is borderline, but post-prandial blood sugars may be elevated. The hba1c and fasting sugar are somewhat discordant. I do think this indicates significant risk for future diabetes, but blood work should be repeated or obtain 2-hr ogtt to confirm. Even if all ok next time, i highly recommend change to healthy lifestyle to avoid worsening.