Fourth sentence: "My nerves are not good."
Saying your nerves are 'very good' actually means the opposite of what you are trying to say. Having "good nerves" mean you're not likely to get nervous or scared. Saying you're nerves are not good means you're easily excitable, frightened, nervous, etc.
Fifth sentence: "I feel faint and I have to take a tranquilizer to calm myself down."
See my note on the second sentence. Also, I should always be capitalized.
I changed 'come' to 'calm' as 'come me down' does not make sense.
The 'me' in this sentence should be written as 'myself'. Using 'me' would be correct if the sentence was written in past tense: "I felt faint and I had to take a tranquilizer to calm me down."
I hope that helps make everything a bit more clear :)
Pretty good, but there are a few errors:
"When I go to a job interview, I blush with embarrassment. My hands start to tremble and my palms start to sweat. I can only stammer. My nerves are not good. I feel faint and I have to take a tranquilizer to calm myself down."
First sentence: "When I go to a job interview, I blush with embarrassment."
'Job' needs an article before it; in this case, use 'a'. This makes it mean any interview.
A comma needs to be placed after 'interview' to offset the introductory phrase "when I go to a job interview". Another example would be: "When I am hungry, I have a sandwich." If you write it as "I blush with embarrassment when I go to a job interview" then you do not need a comma.
I wasn't sure if you meant a job interview or a job interviewer (meaning the person giving the interview). A job interview made more sense though, so I removed the -er at the end of 'interview'.
Second sentence: "My hands start to tremble and my palms start to sweat."
Since these are short independent clauses, you don't really need to place a comma before 'and' (tremble, and), but some people may tell you that a comma should be place in between all independent clauses.
Third sentence: "I can only stammer."
I removed the second half of this sentence because stammering and being tongue tied are basically the same thing and there is no need to repeat yourself.