I'm just starting to play violin and I'm having trouble while tuning it. When i try to tune it to G3 D4 A4 E5 the strings get just too tight, if i try to tune it to G2 D3 A3 E4, they get just too loose, I can't play. What can be possibly wrong?
Your first example is correct. It might feel as though the strings are too tight but that's the way they are supposed to be. It is customary firstly to tune your A string (A above middle C). Then the others - probably E, then D and finally G.
One thing that you need to keep in mind is that the tuning system of a violin does not rely on gears the way that a guitar does; both the tuning peg and the hole in which it is inserted taper, and not necessarily by the same amount, so the only thing holding the peg in place is friction. Part of learning how to play the violin is learning how use enough force to keep the peg from moving when you're done tuning, but not using so much force that the pegs become stuck or break. (Hint: go find a teacher! All students should take at least a couple lessons from a private instructor)