Received half a Syringe of Restylane (0.4cc) to treat both tear trough areas...Not sure if it was enough

Hi Delilah.  We typically use between 1-2 CC's for this procedure so .4 is a very small amount.  What you were seeing was probably swelling.  Was the treatment done with a technique called "under the muscle"?  If not, I would be concerned about getting more injected as this is a very technique dependent area.  If your injector is placing the product deep in the skin under the muscle, then by all means go back for more.  If you only get .4 CC's you may not see value past a few months.  We inject 1-2 CC's to get patients 6-12 months duration.  Good luck.

It sounds like you were under-dosed and it was mostly swelling that you saw the first few weeks, I do suggest you have another syringe to see full result 

0.4cc is a very small amount to the tear troughs.  I typically use cannula injection or depot on the bone in this area and get good results, but use much more than 0.2cc per side.  You may also consider a different filler such as Voluma which gives a little more lift if you are truly "hollow."  Without photos it is very difficult to give a great opinion.  However, I do agree with the other responses that an expert injector, someone with a lot of experience and significant background, is required for treating this area.  I wish you the best of luck, Dr. Emer.

It is
possible that you had swelling under your eyes and that is why you thought it
looked great for the “first few days” but .2cc is a very small and does not
give very much improvement.

In my office
I typically start off by injecting 1 cc of Restylane .5 and .5 into each tear
trough. 2 weeks later I have my patient come back in for a follow up and we
decide if they want or need additional filler at that time.

It is best
to consult with a Board Certified Dermatologist with plenty of experience
injecting under eye hollows.

Restylane for tear troughs is a wonderful tool.  It sounds like you just need a little bit more Restylane injected into the area for a full result.  I would suggest you return to your treating physician to correct the tear trough area.