Although and Period
1. Don't expect to solve it easily. Although we did encounter one math professor at USF.
Can I use "unless or similar" in place of "although"?

2. If you want something, Go get it. Period.
What is "Period"?

Question

Although and Period
1. Don't expect to solve it easily. Although we did encounter one math professor at USF.
Can I use "unless or similar" in place of "although"?

2. If you want something, Go get it. Period.
What is "Period"?

Answer

1. "Unless" doesn't work here because the sentence is not of conditional type. "Similar" doesn't fit either. Since you are Brazilian I will translate for you: "Although" means "Embora" or "contudo". So, it'd be, "Embora nós encontramos um professor de matemática na USF".

2. Period is a dot, like this -> . 
É como dizer "ponto final", "fim da discussão."

Answer

1) No, "although" means "but".

2) 'Period' is American English for 'full stop'. It refers to that dot used to mark the end of a sentence. The person said "period" to emphasise there was to be no further discussion.