Looking at, and judging someone else's photography is always going to be very subjective, but of course, there are always the basic photographic techniques that need to be right irrespective. Focus and exposure just to mention two. When you asking for critique Hannah, its useful if you can include the exif information, including the equipment you are using, that will help us to make constructive suggestions.
There has been some useful comments already, but not knowing how much you already know about photography, I have to generalise a bit and assume your still learning the basics. It will be better for you to study and learn the basics before you consider specialising in in any one genre of photography, especially with all the costs that will incur.
Looking at the pictures, you do seem to be using a wide aperture, if that was intentional or not I don't know, but doing so has given you a very shallow depth of field, and that has been detrimental to your pictures.
The flowers are, as has already been said, rather too busy, and you can see by the flower you have focussed on, that its only partly in focus due to the narrow DoF. The cat looks like you have focussed just behind the eyes (look at the fur detail). The third one, again you have focussed slightly behind the subject, the rock is more in focus than the subject.
Please don't be disappointed with negative comments, there's no progress to be made if you are not told where things aren't correct. From here, I would suggest reading up and learning a bit more about the exposure triangle (aperture, shutter speed, ISO), and the effect that changing any them has on the final results. These are the basics that you need to master before you move forward. If you find yourself struggling with understanding anything, just ask on here, there are plenty of experienced members who will be only too pleased to help.
You have posted some good pictures to start with, and by following the advice given you can only get better, so well done.
Looking forward to seeing some more from you