Very good for a first jam! Hope you learned a lot in the process! I loved your particles, biting the enemies felt very rewarding! Also liked the way you used the sound effects and your pixel art is pretty decent! I think the animation of the T-Rex should change frames a bit slower to match its speed so it doesn't feel like he's sliding on screen (I loved the idea that the legs are on a separate layer, I guess it made your life a lot easier) . And it's always extra points when a dinosaur can shoot fire