I used the good old 'pull out method' to prevent pregnancy and it worked. However...

So my periods used to be very irregular when I was using birth control but in April last year I stopped and ever since my menstrual cycle has averaged 25 days and my partner and I used the good old 'pull out method' to prevent pregnancy and it worked. However on Christmas eve we decided that it was time to start letting nature take its course and see what happens. My LMP was 21st December and we had unprotected sex on day 9, 10, 23 and 27 of my cycle. My usual cycle is 25 days and today is day 29 and still no period. I feel like I'm due on, cramps, backache, fatigue, sore boobs etc. I also have stretchy clear/milky cervical mucus and my cervix feels hard round the edges but mushy on front and is quite high up?? Am I pregnant? I have done 2 tests but they are both negative? Helppppp pleaseeeee