High Vinnie
You can't really overwater when you transplant. The new pot should be soaked completely then allowed to get almost dry before the next watering like usual.
It's likely just a little bit of transplant shock and considering how I treat my plants when I repot they should really show it but rarely do. I'll fill the new pot to the level that will have the soil level about an inch above the rim once the plant is installed as the soil will settle a couple inches after it's been soaked. The plant is already dried out to the point it was ready to be watered so the root ball holds together really good. I'll soak the new soil in the area the plant will sit then saw an inch off the bottom of the rootball with a bread knife to get rid of any long roots. Shave down the sides too if they are wound around on the outside. Then just fill the sides tamping it down with my fingertips and soak the whole thing down leaving it in the runoff for an hour or so to make sure that any dry spots in the pot have had time to soak up enough water. By the next morning they are looking like happy campers and really start growing fast.
Overwatering causes problems when the pot isn't allowed to get dry enough before it's watered again and that happens every time. It needs to dry out a lot so fresh air can get into the roots as they need oxygen to survive. When they are constantly soaked the water goes stagnant and then root rot can get going. When that gets bad the plant can't get water and it dries out which prompts new growers to water even more making it worse. The leaves look dried out and withered, not just droopy like what you are experiencing.
Hope that helps.
