As others have said, been there, done that! If you really enjoy what you are doing, keep trying, and remember that there would have been a time that you may not have noticed that it did not line up perfectly, so that is progress. Just move on to the next row and pin as you go and match the points and seams for each block and if one doesn't match, at the point of pinning, you can correct the row before you sew. Good luck, and just know that like all other things in life, practice is what it takes.