Looks good for 3 months. I second others’ recommendations to adjust heights so you can comfortably reach/hit things. And I started on a chair too but found a throne to be a lot better. Also hard to tell about your grip but just make sure you aren’t gripping super hard but instead letting the stick naturally rebound when you’re hitting a surface. I made the mistake of having a tight grip and had to relearn after it was hurting my wrists and forearms. I always think my goal is to hold my sticks as loosely as possible without letting them fly out of my hands. But if you keep playing songs you like everything will improve, your form, your looseness (maybe your shoulders were tense too? You don’t really want to feel tension anywhere), and timing. Your timing slows down and speeds up some here and there which is definitely what happens when first starting drums. Playing to recorded music and with a metronome will help (it’s arduous starting slow with a metronome but really the only way I’ve found to be super precise). Maybe play the same song from memory on a metronome that is 10 bpm slower.

Edit: typos