Lol, you really don't know what you're talking about, it's not that simple. Finasteride disturbs the endocrine system, it takes weeks before there's good hormonal homeostasis again. Even a small dose of 0.25mg has a strong impact. For example there's almost no difference between taking 1mg and 100mg of fina, the impact on DHT is almost the same.
The point is OP should take some bloodwork to check his base hormonal profile in the case something goes wrong in the future, remember finasteride has an effect on a lot of processes in the body. Everyone should do this before starting fina, duta,... imo.
Btw, this is what FDA recommends when you want to give blood and are taking fina:
The FDA recommends that blood donors taking finasteride be deferred for 1 month