yellow den. leaf
 

I repotted my dendrobium last week. One of the leaves is turning a little yellow. any suggestions on what i should do? And should i be noticing anything to signify a healthy repotting?

Not an expert in dendros, but I don't think it is panic time yet. Leaves eventually turn yellow and fall off--usually bottom leaves first and working up. So this may be just normal aging. It may also be going into a dormant period where it will require very little water as it goes into its resting time. Normally this period falls in the fall/winter season though this will vary by individuals. Seems a bit early for winter dormancy. That said, a very likely explanation is that dendros are notorious for going into a major sulk following repotting. As long as the canes seem to be in good shape following leaf drop, it should recover from its snit and start producing new roots, new canes, and new leaves. Just keep a close eye to monitor the health of the roots and canes.

Hopefully, this response will bump your post up to where others with more experience in dendros will find it and give you more expert advice.