Like you, I'm a newbie quilter so I had no stash of "quiltish" fabrics. I've been bitten by the Fat Quarter Bug and have been accumulating them left and right lately (15 today.) I've vowed now to slow down on just buying random FQ's and to begin organizing the fabrics, colors and patterns I've collected into projects I'd like to do.
I come from a garment sewing background but in a really big way - medieval and Renaissance era costuming. This means that my existing stash is comprised of HUGE cuts of cloth. 10 yards of 60" slate gray cotton velveteen, 30 yards of cotton poplin, 7 yards of an exquisite sapphire blue silk ... you get the picture. I should have quilt backs enough for the next 47 years! I uncovered yet another hoarding spot of fabrics yesterday. It's all being dragged into the living room and stacked up in front of the fireplace for "review and disposition."
So don't do what I've done. Try to stay reasonable about what you buy and how much of it you buy. Fabric is an obsession that can easily take over your world. That's not necessarily a bad thing but it IS a thing you should be aware of and might want to try to control. Be smart about your collecting.
My .02 cents,