Numbness and tingling are unusual prickling sensations that can happen in any part of your body. People generally notice these sensations in hands, feet, arms, and legs. Many things can cause numbness and tingling, including sitting with your legs crossed or falling asleep on your arm.
Meth can stay in the system and be detected in urinalysis drug tests 1-4 days after use. But chronic use can extended this detection period. More here on how meth works and the length of time it stays in your system, with a section for your questions about meth at the end.
Re: drug test, how long does it stay in your system. meth is out of your system in 3-4 days. There is a liquid that my BF used to take 1 hour before he would go in for a test and it would mask the test for 4 hours. There are ways to get around tests.