Thank you for your feedback! You get as many rerolls come to the dice you roll, but you can also purchase one (5 coins) from the shop. You can also gain a free reroll from the patient's quirks (small screen on the up-left corner).
This is the symbol that indicates that you have reroll and you just left click on it:
At the end, you have to memorize the sequence of symbols that appear large on the screen and not the patient's therapy. Maybe we have to make the tutorial more clear in the future. We will look into it.
Thanks for playing our game! We appreciate it :)