Is this Tyndall effect or bruise? (photos)

That appears to be a bruise. However, you will need to wait about one week for any bruising to resolve before knowing if there is also a Tyndall effect. Either way, if you have fullness or discoloration beyond a week return to your physician injector so they can reevaulate you and possibly place some hyaluronidase in that area. Best.Stephen Weber MD, FACSDenver Facial Plastic Surgeon

unfortunately, it may be too early to tell.  At this point, it looks like an early bruise - tyndall gives you more of a light bluish hue.  Keep some ice on it, you can even use a little of topical arnica montana to help remove some of the bruising if it is bruising.  Give it some time to settle down.  When in doubt, always go for a re-evaluation with your injector as depending on what technique was used when you were injected as well where within the anatomy of the tear trough it was injected it may give hints as to what is going on longterm.  Best of luck.