And what exactly DID happen?
The most likely scenario is that you actually spent hours joyfully practicing...incorrectly. Making the SAME mistakes in the same places, playing the SAME note the exact SAME "out of tune-ness" EVERY TIME, confusing a bowing in the SAME place, etc., etc.
Now, you will find that you must actually spend time undoing the damage that you have practiced mindlessly from the previous week. My question to my students is WHY practice incorrectly in the first place? It takes at least TWICE as long to fix these areas once muscle memory and the ear are used to playing this way. Don't even get me started on the problems you will have with your ear from practicing out of tune for a few weeks--that could literally turn into YEARS and possibly forever, of playing out of tune. Why? Because your fingers are now used to playing in the out of tune places, your left hand and arm will be all out, and most importantly, your ear now THINKS it is playing in tune otherwise you would have corrected it!
So, just do yourself a favor and take the time to practice CORRECTLY and that means slowly.
Take a section, lets say the first page and divide it by phrase, or 2 measures, 4 measures, etc. Once you have decided the few measures that you will begin with, the first thing to do is to play everything--Every....Single....Note....Precisely....In Tune. Do not necessarily worry about the rhythms. The goal is to get from one note to the next CORRECTLY. Do not leave a note until you have played it in tune for a least a couple counts. It is a good idea to play along with a drone (See the page entitled, Resources).
Since you are playing extremely slowly, you will also have time to ask yourself, "Am I playing with a beautiful sound, is the connect between string crossings fluid, where is my bow placement (close or far from the bridge), am I playing with a straight bow, is my bow hand correct, etc.
The next thing to consider is the left hand and body--are you tense, do you have a death grip on the neck, are your shoulders tense, are you actually comfortable, are you breathing, are you clenching your jaw, etc.
This is called mindful practicing. Intonation is only one aspect of mindful practicing, we will get to the rest later, BUT only if you can have the discipline to practice Step 1 first.
....and that is all that Master has for you now...may The Force be with you. :)