Will thorazine (chlorpromazine) make me feel crazy?

Circumstances. This depends on the circumstances of using thorazine (chlorpromazine). If it's been prescribed for psychotic symptoms, agitation, &sleeplessness, i agree it could help you feel better. Low doses are sometimes used for severe nausea too. But if you've obtained this illegally -- and are just trying some for experimentation -- yes, it could be a weird experience. You'd be disturbing normal brain chemistry.
Usually the opposite. Thorazine (chlorpromazine) is one of the oldest antipsychotic medications, having been around since the 1950s. It treats symptoms of so-called 'craziness' = delusions, hallucinations, disorganized thoughts and behaviors. It has psychiatric & medical uses including: treatment of schizophrenia, bipolar disorder manic phase, agitation, nausea/vomiting, intractable hiccups, & insomnia resistant to other treatments.