Is 30 days long enough for weed to get out my system?

Weed. Frequent heavy use of highly potent drug will take longer.
Depends. It depends what you mean by out of your system. Even a heavy cannabis user should be able to pass a drug test following one month of abstinence. Depending on the potency and frequency of use, it can take several months for a person to be "back to their old self" after quitting weed. Each day will get better and better. Hang in there.