Here in Portugal the tomato wasn't yielding that well this year if it makes you feel any better. This weather is fucked up, I'm a gardener, and I see the plants are confused, fruit trees giving fruit 4 months before they are supposed to. This climate situation we are going through is very abnormal, and plants can feel it to.
Tomatoes are also my first try and currently waiting for a Third round! I also planted Pimiento Habanero, passion fruit, lettuce, basil, coriander, and cannabis being the latter the most difficult one to care for, without a doubt. I have been feeding them home made plant food that I made based on coffee leftovers, ashes, potassium with banana peels and sugar, and some other ingredients that I learnt to use as nutrients. I am very happy with the experience and the result. Still ongoing tbh!
I bought them on a French speaking place. Can't remember the exact name, sorry. If Im not wrong they are "Bœuf Tomat" that translates as Beefsteak Tomato after a quick Internet search.