Eye drops have very little, if any, systemic effects so would not be expected to affect blood glucose measurement.
Symptoms such as weight-loss and peeing a lot only occur with very high glucose levels so even if a drug could somehow affect glucose measurement, it wouldn't be able to mask such high levels. The symptoms you list are non-specific and can be caused by other diseases - hopefully you will have had blood tests to rule them out (not just tests for
diabetes).
There may be several reasons for this, your optician should be able to identify the cause.
The eye drops can cause increased skin pigmentation around the eyes in some people.