Firstgrow

Yes, over watered and over fed.
In soil it should be a schedule of plain water/plain water/feed/plain water/plain water/feed.....so that the plants are only being fed every 12 days or so, not every time you water. The plant needs to use what is already there, before new nutrients are added. Soil "holds onto" fertlizers better/longer than what other substrates do, hence the need to feed only every third irrigation.
When it comes to watering, water deeply to run off, that is, water coming out of the bottom of the pot, then don't water again until the top 3-5cm/1-2 inches has dried out again. Sticking your finger into the soil makes for the most accurate moisture meter there is!
It is a common mistake to just water to a plan, like every three days and always give X amount. Many things influence a plants water requirements, like temps, air flow, plant size, water holding capacity of the substrate, humidity, plant genetics etc which all determine together how much and how often to water. In time and with more experience, you will eventually develop a "feel" for this and will "just know" when and how much to water.
In the meantime, feed every third irrigation and only water once the top inch or two have dried out and you should be on the path to success.
At this size, probably half a gallon at a time would be in the ball park.