Help advice needed

Not at sure this is the right place to post and hope I don't upset/offend anyone when I say I'm not ttc but I need your pearls of wisdom.
I'm currently in a loving ltr and on the pill, we are both late 30's, neither of us want more children (not that it would be the end of the world if it happened we just feel we're too old) and that's why I'm on the pill...please bear with me....
I was on antibiotics during first two weeks of December my doctor didn't say there was a risk of this invalidating the pill but we used the withdrawel method. My 7day break was due to start on the 10/12, I came on on the 11/12.... No problems so far. I was due to start taking the pill again on the 17/12 but there was a mix up with my prescription (long story) and therefore I started taking it again a week late (the 24/12) again we did have unprotected sex during this time but only once I'd took my first pill. If there had not been a delay in taking pills I would've been due for my break on the 31/01 and expected to come on on the 01/01 but due to the delay I carried on until the 21 days were up, taking my break on the 13/01. I didn't come on Saturday and still havent. I have felt really quite unwell this week, queasy at certain smells, upset tummy when I eat bit not sure that my mind isn't playing tricks. I do have sore boobs but that's not unusual if I'm about to some on, I've also hade mild cramps but they aren't like period pains, they seem different.
I don't know if this is just because my cycle is confused, my dp is jokingly shrugging it off but I don't know. I'm also worried as have drunk lots over the holidays, ofgs I'm confused.