Are you keeping it in the house? It will need good light. Meyers can take 40's but don't really like to go much below that. It can be out in the daytime. Sudden changes in light will make most trees lose leaves so it is best to put it back in its normal home in the daytime if it is warm.
Test the soil for dampness. Citrus trees can take deep watering but don't like wet feet. Mine are planted in pure black cinder so it drains very well and needs to be watered everyday or two. If I don't water by the 4th day, the leaves start to curl. My oldest potted tree is almost 20 years old, the youngest is probably around 2-3 years old (I bought it this year). The small ones are in gallons and the largest is in a 20 inch pot. Some are in between in 5-7 gallon pots. I have kaffir lime, calamondin, Tahitian lime, yuzu, Meyer lemon, Satsuma mandarin, and a Eureka lemon. Some I have in multiples like calamondin, Meyer, and Satsuma. The Yuzu, Kinsu, and Eureka I have killed before so I just get one of those at a time.
Happy gardening in Hawaii. Gardens are where people grow.