My mistakes etc.

I find myself using "etc." a whole lot in writing (in Ratology).  Two questions that came two me were whether I need an "and" before "etc." and whether I need another period if "etc." is used at the end of the sentence.

Apparently, I am not along on this planet with these questions--which made it relatively easier to find the answers:

1. There is no need for an "and" before "etc."  "Etc." is the abbreviation for the Latin expression et cetera where "et" means "and," and "cetera," "the rest".  Thus, saying "and etc." could be like saying "and and the rest"--the "and" is therefore redundant.      
2. Don't double up periods.  One period is enough--the period after the abbreviation can also serve as the period.  It is also recommended to write the whole phrase out or to avoid placing abbreviations (e.g., etc.) at the end of sentences.  Yet, when the sentence ends with either an exclamation mark and question mark, you need to keep both punctuation marks. 

In the processing of searching for the answers to the aforementioned questions, I found more issues that I were not even aware of...

According to the Chicago Manual of Style, "etc." is preceded by a comma and should be "(unless it ends a sentence) followed by a comma when it is the final item in a series" (6.20 Commas with “etc.” and “et al.”).  "Etc." should also not appear "at the end of a list that begins with e.g. (or phrases similar to such as, for example), which properly introduces a short list of examples."  In addition, "[etc.] should never be used in reference to people... (and indeed it should be used only after at least two items, never just one). But often writers seem to run out of thoughts and tack on etc.for no real purpose." 

Also, as per the definition of "etc." on dictionary.com, "etc." is "used to indicate that more of the same sort or class might have been mentioned, but for brevity have been omitted."  The way I read it... though it can be a catch-all phrase--it can only be a catch-all phrase for things of the same class (e.g., fruit, animal, dinos).  Yet, don't use it if people are unfamiliar with the items with the class.

I am going to end this post by identifying the mistakes I have made so far in my life concerning the usage of "etc.":

1. Put an "and" before "etc."
2. Might have put an additional period after "etc."
3. Might have not put a comma after "etc."
4. Left out the period for the abbreviation.
5. Used "etc." when the list began with "e.g.," "such as," "for instance," or "for example."
6. Used "etc." in a list with less than two items.
7. Used "etc." simply because I ran out of thoughts.
8. Used "etc." when items in the list might not belong to the same class.

So it is--my preferred Bad English is my preferred Bad English and mistakes are mistakes.  My lessons learned for the day--mistakes etc. 8-O lol

References
http://dictionary.reference.com/browse/etc
et cetera
Ending a Sentence with an Abbreviation
Ending a sentence with an abbreviation [duplicate]
http://www.chicagomanualofstyle.org/16/ch06/ch06_sec020.html
http://www.columbiaseminary.org/coffeetalk/035.html