High sugar level

Lili

Recently I went to the doctors and got my blood taken out to check it and my sugar level was the only thing that came back high. I’m 20 years old and eat pretty average however I do tend to eat a lot of sweets. The few days before I got my blood taken out I had eaten a chocolate chip peanut butter cookie every night with milk. Could this have caused my sugar level to come back so high? I’m really nervous now because I’m generally a healthy 20 year old.