Shrimp swim like crazy after water changes. They also do when something is killing them. Is the planted nano tank newly set up? The substrate, decorations, etc could be leaching something. What is the tank's history? Did you EVER use it as a quarantine tank or treated with medications, especially copper based ones in it? Do a water change and see if their condition improves, or, if possible move them back to where you know they are safe(the old tank?)