By day 4, the fermentation slows down and it's time to rack the wine to secondary- a carboy, and top it up and airlock it. Fermentation stops because the yeast eat the sugar and then are just about finished.
You absolutely need a hydrometer, and should take readings before fermentation starts (so you know if you have enough sugar, or too much) and when it ends.
Adding more sugar was probably a mistake, but if you already did it's too late to change it now.
Just see if it starts again. If it does, you may end up with some hot tomato rocket fuel. If it doesn't you may end up with sweet tomato wine. Either way, wait a few days and see what happens. If fermentation doesn't start back up, make sure you rack it to a clean sanitized carboy, top up to the bung, and airlock it. Let it sit for 45-60 days, and then rack it to a new carboy as tomato wine will throw a ton of lees for a long time. By then, it should be clear, but will still throw more lees so you'll need to rack a couple of times.
I have my tomato wine recipe posted (on the left, under my avatar in the recipe pull-down) if you want to see my instructions.