 [ Symptoms ] one hit of weed 2 months ago and before that one hit of weed in may will i fail a hair follicle test [ Disease ] maybe that depends on the sensitivity of the hair test and the amount and location of the sample taken very tiny amounts of cannabis may not be detected but i have no idea if you have a sufficient amount in your hair follicles to register a positive result be prepared the test could be positive or negative cross your fingers and lay off the weed if you know you may be drug tested