I was just like you when I first started quilting many years ago. Then I got Mary Ellen Hopkins book "It's OK If You Sit On My Quilt". She talks about your "PPM", which stands for Personal Private Measurement. As long as you are consistent with your seams, it's OK if it's off a little. That freed me from the stress of not having an exact 1/4 inch seam. Are the quilt police going to get you if your quilt does not measure exactly as the pattern states? I figure as long as I'm not out to make the perfect quilt, I'm good to go. I will never enter my quilts in a show, that's not why I love quilting. I just want my family and friends to be able to snuggle under something I made for them with love.