1970,
A blood glucose reading of 5.5 is excellent. Therefore, should you mean 'funny' as in feeling hypo, there may be a explanation.
As Synonym has said, you havn't give us much to go on here, but lets say that you are normally running high numbers (bg's above normal target range or higher) you may be starting to feel a 'false hypo' coming on at this level due to your usually elevated levels. Hypo's are normally considerd to be 4 or below, but for people that have had bad control and suddenly tighten their control, it can take the body time to adjust to the new lower readings, so should this be the case with you, this could explain things quite clearly.
Should you have any concerns about these episodes, I would suggest you contact your gp or diabetes clinic, remember not everything can be related to diabetes, so if unsure seek advice.
Nigel