Is this child abuse???

ok so my mom is crazy, she puts me on time out instead of grounding me and im 12. except the crazy thing is that its ATLEAST 2 hours! when i was real young she used to wack me with a belt or a hanger when i was bad but when i was 9 she stopped and instead put me on like 5 hour timeouts, probaly atleast 3 times a month , USUALLY more! but when i say timeout i mean she leaves me outside of the house with nothing (sometimes i sneak my skateboard out) and i have the freedom to walk anywhere i want. its usually for really stupid reasons too, like if my posture is bad, if i break a crayon, if i use too much paper towels, if i squeeze out i little too much paint on accident. shes very chineese and cheap and she neevr waistes anything, and even when i accidentaly break a pencil she has a tuntrum. she favorites my brother, she only does this kinda stuff to him like twice a year and its never as worse. it dosnt seem like shes trying to help me become a better person. she says she dosnt want to see my face. i am sooo mad like she cant do this to me, i have 911 on my speed dial list. is this child abuse??? oh and sometimes she threatens to chop of my hands (she never does it)