Your glucose goes down because insulin came in to clean up the left over glucose, which means your insulin is doing what it is supposed to do?
If your not feeling ill or symptomatic (reactive hypoglycemia), then your probably ok?
If your a sugar burner that may not be such a good thing[1][2]?
Dr. Berg always recommends snacking on a little bit of protein (but not too much) if feeling hypoglycemic (do you feel ill at all? e.g. faint, dizziness, headaches, migraines, and others) rather than eating a tube of glucose or sugar!
References:
[1] “…Reactive hypoglycemia is the general term for having a hypo after eating, which is when blood glucose levels become dangerously low following a meal. Also known as postprandial hypoglycemia, drops in blood glucose are usually recurrent and occur within four hours after eating. …” …More
Note: “dangerously low” what may be dangerously low for one person may not be dangerous for the other person and the differences between a person on a ketogenic diet and a person who is not?
[2] Reactive hypoglycemia: What can I do?