Your native language is Spanish, you know French and English, and I don't think it was difficult to learn them, because they resemble each other. Russian differs them, it is a challenge, it is another way of thinking. If you want to know Russian mentality and overcome the difficulties, you have to learn Russian. (By the way, it is a reason why I am learning Japanese. And I really enjoy it).

All right, it is a good question to think about. I don't really think that you should learn Russian if you don't work for an international organization, corporation, company or something like that. I do belive that this is a very good language and very beautiful but it's not situable for just an usual hobby. There must be something else that attracts you really much in Russian if you decide to learn it. Well... honestly, I don't see a reason to learn Russian. And it's a very difficult language. So... you have heard one of possible opinions. :)

If you have some doubts it means you don't want to learn Russian otherwise you wouldn't ask, you would learn it hard.

Good luck to you in learning Russian.

I dont see any reason why not =)