Hi Prabha - Without more specifics, it's somewhat challenging to answer your question.
However, in the most general of terms, typically droplets in oxygen tubing may be there from a humidification device that is in use.
If you are able to provide more detail, we may be able to provide more of an answer.
If you are concerned ('alarmed' as you said), about these droplets, I would suggest you contact your equipment supplier to make certain everything is working properly.
Please do check back and let us know how you're doing.
All the best,
Leon (site moderator)