If you are pretty sure he has the flush, then you have 7 flush cards, 1 T, 3 Aces, and an additional 6 cards to pair the board twice to give you nut flush/boat.
So that is 17/44 = 39% to win the hand on the river. So then just figure out what pot
odds you were getting and you can figure out whether or not putting him all in was good or bad.
However, if you are pretty sure he has the flush then you are better off flat calling the reraise because you could save some money on the river if he value bets, or potentially make a good lay down if you think he has you beat enough times there to make a river call unprofitable in the long run. Since you say you lost $250 on this hand, you must have been pretty deep and most likely wouldn't have had to commit your stack for this hand had u just called the reraise (unless you hit nutflush/boat obviously). A problem with shoving in this situation is that you have very little fold
equity.
Now, ok it makes sense to fold with 3 cards of the same suit out already, but if there are 2 cards of the same suit and you have a good hand should I bet whats in the pot to get people chasing a flush to fold? But, what do I do when people chasing a flush do call me or how would I even know if they have a flush or not.
No you should absolutely never fold this hand to a min raise. You are getting phenomenal odds to draw to the nut flush/boat if nothing else. Shoving all in when you are 1. very deep 2. quite possibly behind in the hand and 3. have basically no fold equity, is not really the move you want to be making however.
As for the rest, you don't have to bet the pot for ppl chasing a flush. If you are vs a calling station, then you want to bet more (so pot size is probably fine) to extract more value, but you have to bet less than 1/2 pot to give somebody with a flush draw odds to draw to the turn from the flop or the river from the turn. So 2/3 or 3/4 pot etc is fine. And you can't know they have a flush for sure, you can just estimate what range of hands they will be making the same move with and figure out what % of those hands you can beat and from that you figure out the most profitable move to make.