charmednmissouri

I am following the class videos. Have looked thru the class notes and discussion listed. I do not see others having mentioned the trouble I am having. I have done a google search for this quilt, not finding any discussions about it.
Now for pictures. The first picture is the result with the triangle sized as the pattern calls for. It is just too small. The second photo is the result when it is flipped in place as the pattern mentions. You can see it is obviously too small.
So I made another triangle, large to make sure it reaches, thinking I could trim it down.
So I laid out the the 2 pieces of the block together and thought "ok, this will work" Until I measured the block with the 2 pieces together, unsewn but allowing for a seam allowance to join them and it is supposed to be 17.7" but measures out to 21+.
I am truly to the point I might throw the whole thing into my orphan block box and later just cut it up/design another block. I have never encountered a point where I am ready to throw up my hands on a quilt, but today seems to be the day!
The last will be of my y-seam gone wrong. But I admit, this is not a strong point for me, I have maybe sewn a couple of them in my lifetime, so I will admit, on that, I am a newbie. But I did try to watch as many videos on it and thought I had it. So I will rip that out and have another go.