@Nikola ********
okay here's how that works.
Once you go onto amnesty <- (meaning your original entry stamp or extension stamp ran out) you CANNOT go from amnesty to ANY visa type inside the country :O
In order to apply in country at the immigration office for a 90 day Non-Immigrant type visa, you need between 15 and 21 "real days" left on your entry stamp (from a 30 day visa exempt entry or a 60 day tourist visa entry OR an extension from one of those entries. That's beause when you apply for an in country 90 day non-immigrant visa the application goes under consideration between 14 and 20 days (depending on the immigration office you apply at) and then you go back to get the Non-Imm visa and the new 90 day stamp inked into your passport. That's why you need that many days left on your current stamp.
As you are on amnesty you CANNOT get a Non-Immigrant Type B visa inside the country