Welcome to the site Silver. Those animations look quite good. There's a bit of shakiness in the spacing (movement from one frame to the next), which means that the spacing amount is inconsistent in areas.
Example of shaky spacing ("|" = frame, "-" = spacing amount):
|-|-------|----|------------|---|----------|
Smooth spacing:
|-|--|----|--------|--------|------|---|-|
You could also start learning to ease, which is the slowing down and speeding up of movement. If you use the principle of how a car never starts straight away at full speed, and that it needs time to build up it's speed, you'll see that basically every movement uses easing in some form.
I also highly recommend
Mitch's tutorial which covers all of the basics. Nice stuff so far though.