An interesting bit of writing, but as Mesarthim stated, there are a few errors. Not in what you said, but rather the specific words you used.
1) “thanks to my job I have learnt to smile..." While 'learnt' is used in American to represent an uneducated person, usually a farmer, cowboy or other rural type, the proper word is 'learned.' In this case, "... I have learned to smile..." Since you are implying the character is in a school of some sort, I would have to assume that more proper English is used by the protagonist; unless she's actually trying to act uneducated.
I also want to note that "Housewifes" should be "Housewives." Words ending with an 'eff' sound, like 'wife' or 'self' changes to a 'vii' sound when meaning more than one, such as 'wives' and 'selves.'
2) The entire paragraph was filled with punctuation errors: "Eva Longoria said in Desperate Housewifes, “Thanks to my job, I have learnt to smile even when I don't want to”. Thanks to my current job, I also have to smile even though I feel like the most pathetic human being in the world. Thanks to my future job I will also have to fake a smile too (Also and too carry the same meaning, but in this change using 'also' ahead of the phrase sounds better in English.) so my patients feel good. I’m supposed to be the strongest link in the chain, aren’t I? But I’m not strong enough. So here I am, like a whore from a dead end brothel, in Javier Roldán’s office." I boldfaced the added punctuation, but I'm not sure how visible it will be. Maybe I should have colored them as well. I also changed a few words to ones sounding more natural.
3) - It’s a pity that such a beautiful woman fails the exam. The more correct term would be 'failed' since the test is over. 'Fails' is usually used as a future tense, as in "If he fails the exam, he wil have to take it over."
4) I lean on the table slightly, I have to make sure that Roldán sees my low, low neckline. I envision you want to emphasize the cut of the blouse, rather than how short her neck is.
5) - why the hell have I damped my lips with my tongue? I think the word you wanted to use was 'dampened,' but a better word would be 'moistened,' which implies wetting them to make them shine. While 'dampened' works, it carries a less--erotic--connotation.
6) He poses as a gallant, and as long as there will be people like as me that sells themselves anyway, he will be justified. I can't fully explain the difference between 'like' and 'as,' but in this case 'like' is the word you wanted to use. As for the word 'sells,' your sentence uses a plural subject, "...people like me...," which requires a plural verb, "...sell themselves..." Note that you used the proper 'f' to 'v' shift here in the word 'themselves.'
7) I lie on the back and cross my legs... May I assume you mean, "I lie on my back and cross my legs..."?
8 ) He comes across crosses to the door and locks it.
9) I guess he refers is referring to the few buttons that still keep are still buttoned.
I may have missed one or two others, and maybe I should rewrite the whole thing to demonstrate the corrections better. However, I'd rather see if my notes were clear by asking you to rewrite it yourself. (Honestly, I wouldn't be surprised if you shot me instead.)