Welcome to the Watercolor Forum. This is a very nice seascape, you did a really good job with the cliffs.
Some compositional elements you might think about in future paintings are the horizon line (it should be straight but it appears to slant from right to left here).
Also, the horizon line and the top of the cliff run into one another. This is called a tangent. It would have been better to have the horizon stop a little below the top of the cliff instead of continuing the line. Finally, the line of plants and flowers across the front of the painting stops the viewer's eye from moving into the work. You can have elements like that in a work, but it is best to leave some openings in it.
I must say I am impressed at how well you did painting this on canvas. I only tried using watercolor canvas once and was frustrated by it.