First of all, breathe! Next, I need to clarify, are you using a quilting foot (the small, round or oval shaped one that most likely has a spring on it), or are you using a walking foot? If you are using the smaller, round/oval shaped one, did you drop your feed dawgs? Because with this foot, you are in control of your fabric, not your machine, and so the fabric moves as you move it. Quilters gloves are good to help keep your hands from slipping on the fabric and thus move your fabric more smoothly, at least for me. I know some folks don't like them, but I can't quilt without them. If you are using the walking foot, you might try adjusting your pressure foot tension, if your machine will allow you to do so. When you quilt, you'll be pulling the pins out while you are quilting each section and using the quilting gloves should help you keep control of the fabric so bunching on the back shouldn't be a problem. I also find that spray basting helps me a lot better than pinning, especially on smaller quilts (I think spray basting doesn't work as well on larger quilts because they are heavier and the spray is just not that meant for that).

If you are planning on doing just straight, stitch in the ditch type stitching, I would recommend using the walking foot and not the quilting foot ... your stitches will be much straighter. The quilting foot is generally used for free motion so you have the freedom of moving the piece in curves, and circles, and all sorts of directions. I am more of a free motion kind of person, and tend to do more of that than stitch in the ditch. But I think the kind of pattern you use, whether you draw it on with chalk or fabric marking pen, or if you free motion, or stitch in the ditch, or whatever is totally a personal thing and what you feel comfortable doing. I find following a pattern is harder than doing free motion, but that is me. Others need the pattern drawn on. I don't think the quilt police will come and get you, so look at your piece, and quilt the piece as you are comfortable and seems to flow with the pattern you have chosen.

But most importantly, breathe, relax, and have fun with it.

Best wishes