How to Get Minecraft Back?

So I paid and downloaded Minecraft on my PC. I tried installing a mod for it, and when I did, I think I either misclicked something, or I just did it wrong. Anyway, when I tried to play Minecraft, it said I could only play the demo and my profile was set to "default".

Now I can't play Minecraft at all. Even the demo won't work. I was wondering if there's anyway to get it back without paying the whole $26.95 again. If so, how do I get it back? This whole ordeal happened about 3-4 months ago, just so you know.

Click on the drop-down tab and select your profile or completely delete Minecraft from
your computer and go to http://www.minecraft.net/...craft.net/ and download the client, login and have fun bro!