This is getting irritating

I know you are getting a bit annoyed at me for posting about AF all the time but the bloody bitch hasn't shown yet and it is really starting to get on my nerves. I am afraid of what the reasons might be. It's either 1. I am pregnant or 2. my cycles have gone to shit (again) The thing that worries me a bit is that normally I am a bleeder. If my cycles are haywire then I tend to bleed for very long. In other words AF overstays her welcome and the arrives late the next month but this month it's totally different. She arrived on time last month and left again after 4 days. Now this month she doesn't even bother to show. I have chosen to stay in denial for a bit longer before resorting to a HPT. I don't know what I'll do if I see two lines, so for time being I am not even going there. We'll give her a few more days. The thing is I will be absolutely flabbergasted if it's the case because we mad use of the "rubber barrier" kind of contraception. I know it's not 100% safe, but after all we are infertile!! These things don't happen to us. We usually have to have the timing just right , the Low GI diet in order ,the perfect cycle, correct medications, the BD together with a certain time period of elevated hips, to even start hoping for AF to be late.
So I think I am fairly reasonable when I say it's impossible!! Or what do you think?