I just did my fillers a week ago and i didn't see any improvement in my eyes. The area under my eyes became darker and more fine lines appeared. May I know what might have caused this?

There are no photos provided so I will be just making an assumption.

I presume the fillers were injected in your undereye area to improve your tear trough. The possible reason for this is what is called the Tyndall effect.

This is due to hyaluronic acid fillers being injected too superficially into the skin and or in too large quantities. This results in a bluish discolouration due to the light reflecting off the filler particles with increased scattering of the light. Thus, the area treated looks darker due to the discolouration.

Hope this helps!

Regards
Dr KK Chew