Hi meowcatninja. If your pics show the layout of the three triangles, it looks like you don't have the triangles in the proper orientation. Double check your position for the three triangles. That is, the cream triangle goes with the long side down and the short side of the purple triangle attaches to the left short side of the cream triangle. Then the third triangle attaches to that.
Triangles don't always match point-to-point. Mark the center of the edges you are lining up and work out from that.
Hope this helps. If not, post pic of the block showing it complete so I can see all the points.
It's Quilting! You're supposed to be having fun!
Thanks MizPat. I got those Fons & Porter triangle templates so I can trim the ends and not have problems but theses triangles meowcatninja is using are different