First - I would look at all that you have done right! Your colors are lovely and go together very well with good contrast which is half the battle Your block is sewn together, it is square, all of the pieces are in the right place and turned correctly, and it doesn’t appear to have puckers. Each of those things are big accomplishments!
Constructive critism of anothers work is hard because we try so hard to be positive and supportive. You are getting some great feedback so I will only add a few thoughts; no one is perfect so don’t expect to achieve that right off, pick an area or two you feel need improvement and focus on those for the next block, use internet searches to find a wealth of ideas and techniques to improve. You may want to google how to nest seams and find a great technique that works for you.
Have fun and enjoy the process of making a quilt. Mistakes happen and here we call them design choices! Great job!