Don't be so hard on yoourself. This is a fine looking top.
Suggestion. I presume you are already pinning when you are sewing across seams. Someone mentioned this tip to me. When you pin, consider which way each seam allowance you are crossing goes. The one on the top should go towards the needle, the bottom, away. If you do the reverse, the crossed seams will tend to be pushed apart. With this, they will be held in place. Sometimes, in doing this, I find I have twisted the seam allowance. I then clip the allowance (once) so it will lie flat. A year or so ago, my guild was making a project together. Several quilters who are more experienced than I grumbled about this problem. after a quick hint, they all made perfect seams.