We really want to help you but it is really important that we have all the information regarding your residency. That's why you got so many confusing answers, since it was very unclear to us when you were where.
First of all: When you return to Canada on - let's say - February 28th, 2016, the border officer will likely assess your residency situation. At that moment he doesn't care as to when you are leaving in the future and what your plans for 2017 are. All he or she wants to check is if THEORETICALLY, you could still fulfill the requirement from now on.
Also, never do any calculations in years, months or weeks. Always count days, nothing else!
So let's have a look (all dates are of the form YYYY-MM-DD)
You became a PR on 2012-04-24.
You were in Canada from 2012-04-24 to 2012-05-11. That is 17 days.
You were in Canada from 2014-01-19 to 2014-08-09. That is 202 days.
That means that you spent a total of 218 days in Canada.
Your first five years as a PR end on 2017-04-23. If you enter Canada on 2016-02-28 and do NOT leave after, at that five-year-mark, you will have been in Canada from 2016-02-28 to 2017-04-23. That is 420 days.
That means, by the five year mark, even in the best case, you only manage to be in Canada for a total of 638 days. That is below the minimum of 730 days.
The validity date on your PR card does not have any meaning regarding the residency requirement. It just means when you have to renew your card. It's the same with a passport: Just because your passport has a validity date, that doesn't mean that your citizenship would end then.
This is what would happen: You will be able to board a flight to Canada with your valid PR card. But once you are at the border in Canada, one of the two things might happen:
Option 1: You are lucky at the airport
You might be lucky that they won't ask too many questions and just let you through and you can enter Canada. In this case, you can live your everyday life in Canada and nobody will complain but it is important that you cannot leave Canada until you reach a day on which you were in Canada for 730 days out of the last five years. Based on your data, the earliest that would happen is on 2017-08-09, because then you will have been in Canada for 202 days (in 2014) and for 528 days (in 2016/2017). Note that the days in 2012 won't count anymore then since they are more than five years ago by then. Once it is August 9, 2017, you can apply for a new PR card.
All this stuff about Option 1 is what other posters meant with "wait for two years".
Option 2: You are not lucky at the airport
It is very possible that they will ask you about your residency and then realize that you cannot fulfill the residency requirement in your first five years. In that case, they will let you in but report you for a breach of your residency requirement. After that, you would have to fight for your PR status or at some point they might ask you to leave Canada. For these cases, you should get a lawyer.
Important: Never ever lie to a border officer about your residency. Don't say, for instance, that you have been in Canada in 2013 although you weren't. They can confirm that within seconds through their electronic system.
I hope this clarifies things. Keep in mind: Nobody on this forum can tell you if Option 1 or Option 2 will happen. That completely depends on the situation at the airport, who you speak to and how thorough he or she is.