Understanding Menstrual Irregularities and Available Options

Question
It is a bit long but I am suffering from lots of mental stress because of lots of nonavailabilities near to me. I hope, I will get a quick reply from you.

I am 22 years old and because of my menstrual irregularities I have been taking ovral G (Ethinylestradiol & Norgestrel Tablets I.P.) since September'08. My period was almost coming to be regular. I had the last irregular period on 1st September and started taking Ovral G as prescribed from September itself (I forgot the exact date from when did I start). Then I had the period on 10th October and then 8th November. I have completed the 3rd and final pack of Ovral G on 3rd December and my period should come around 6th to 10th December (as I am expecting). But I have had sex with my boy friend on 20th November (i.e on the 13th day from 8th Nov and if I was ovulating on that day!). I have used vaginal contraceptives and pull-out. But I am worried if all these fail because, I saw some red spotting on 25th November as I would have little bleeding on 24th Nov (could it be implantation bleeding?) without any pain. After that I am not experiencing any bleeding of that kind.
My period is now due already. I want to know the probable cause and consequences of my bleeding on 24th. Is it because of dryness by Ovral G or do I get pregnant? We are monogamous and hence there is no chance of STD as we feel. We had similar unprotected sex six months before. But that time I was in safe period. Moreover I have just come to know that the major compositions of Ovral G - Ethinylestradiol & Norgestrel, are used in almost all modern formulations of combined oral contraceptive pills. Does it mean that it worked effectively as emergency contraceptive and hence the bleeding on 24th?
Please say some words of relief to me prior that I may miss my period.
If I miss my period I want to terminate my pregnancy anyhow but not by surgical abortion. It is said that chemical abortions are effective within 49 days of LMP. So with this calculation I will be completing 49th day on 26th Dec. In between these 10-26 Dec I need to undergo chemical abortion. Is it safe without doing pregnancy test? And please inform me if I can do pregnancy test at home on my own with some alternatives without using the pregnancy test kit.

Answer
Hi Bebi,

I found your question in the allexperts question pool. So evidently, whoever you asked the question to did not answer for some reason. I just found your question and realize that it was a few days ago. Since your whole situation could be different now, I am requesting that you email me privately at DCHERYL51@yahoo.com so we can talk at length. Please let me know where you live and your situation now. Hope to hear from you soon.

Sincerely,
Diane Cheryl