I'm in agreement with Deb, too. It 'looks' like your seams may be too deep, more than 1/4". Does your pattern call for 1/4" or a scant 1/4"? Have you measured your seam width to make sure it is what your pattern calls for? Some directions will call for a scant 1/4" when you have so many pieces in a block, but others do not. Consistency is what matters.
Also, what type of thread you use for piecing can make a big difference on the outcome, too. Many quilters have switched to using 50 weight 2 ply for piecing instead of the traditional 3 ply. It makes a HUGE difference!! My piecing has improved tremendously just by switching to a 2 ply, like Aurafil or any other 2 ply. They are just as strong as the 2 ply, but thinner so they take up less room in the seam.
I've pieced a lot of blocks similar to the ones you're doing, and it does look like, as Deb mentioned about the alignment, that your seam might be too deep, more than 1/4".
Be patient, checking these few steps will go a long way to improve your piecing, as will practice. As another poster said, you are doing a fairly complicated block, so please, don't be so hard on yourself. You will be much happier with the end result if you rip and redo once you've found out what's causing the misalignment. Best of luck and please, keep us posted on your progress.
Karla