Jenel.. First off - con gratulations are in order - you have stepped into a world of beauty and fun and comfort and friendship - not to mention adddictions to fabric and thread and tools and rulers and blades and .. oh, OH got off topic there!
Often you will see the instruction to sew a "scant 1/4" seam. That means be sure you don't make the seam more than 1/4, a thread width less is SCANT .. as seams are sewn in, fabric literally disappears! When the seamed fabric is folded over for pressing - there is fabric thread in there that goes with the seam, and makes the block surface smaller if you made that seam a fat 1/4". A specialty foot called a 1/4", or piecing, foot is a great help, but be sure if you use one, sew several practice seams so you know exactly where that 1/4" lies. If the foot edge gives a bit or isn't straight up and down you need to know that and if necessary make adjustments.
If each seam is off by 1/8" - at the end of 8 blocks guess how much shorter that made the row of blocks!
I drew a line 1/4 on a piece of stiff paper, put that paper edge in my machine and sewed with an unthreaded needle. One foot the holes were ecactly on my drawn line, the other foot it was slightly on the edge of my line. I changed it to another machine and it was fine.
Be sure to finish a project on the same machine you started with - all machines are not all the same.
Now go have fun :)