If it's any comfort to you (although I suppose it won't be) virtually all of us who built a PC for the first time experienced frustration in one form or another, although rarely did it extend to demolishing one's computer case or destroying other components out of anger.
So take some deep breaths and get a hold of yourself. The best is yet to come I can assure you if you persevere and clear your mind of nonsense.
We always encourage first-time builders that whenever possible to try to consult with a friend/acquaintance who has either had some personal experience building a PC or at least some knowledge about the subject. The ideal situation, of course, is to have someone at your side from time-to-time to check your work and respond to...