First timer here! GD/ scared to death.

So I passed my three hour by a hair, but they failed me anyway since I was so close... They want me to test one hour after each meal and then a fasting level... All my numbers are below 100 during the day but, in the morning after fasting I've been between 86 and 90😳 this scares me... Is it normal? What are your fasting numbers? Is 90 considered high? Thanks in advance