I can totally relate to that feeling, just in general in terms of spending a large sum of money (and by large, I mean like, over $50 hahaha). It's good that you're nervous and cautious - it means you aren't an impulse buyer and that more than likely you've thought this all through!
As long as you're sure that you'll be happy with what you purchase, I say, just take the plunge and go for it. You'll worry yourself to death otherwise.
Even if you don't make trillions of dollars in the long run, you'll still have animals you are proud of and a new piece to your collection. If that is worth it, to you, then go for it.