IVF - soreness and progesterone?

[tumbleouttabed]

Hi all, I have never posted before but have been gratefully reading many of the threads in this section. I am in the 2ww following IVF (FET of day 5 blastocyst) for 2ndary infertility. DD is 3 going on 4 (had no trouble conceiving her naturally). I have been taking the oestrogen tablets and progesterone pessaries prescribed by my clinic. Now, 5 days post transfer I am starting to get a sore perineum and rectal area. (Sorry if TMI - may as well go for it for my first post....). This is not from taking the pessaries in themselves as I am doing those vaginally. I do often get a similar symptom in my natural cycle normally at about a week before AF. So (a) does anyone know if this is a side effect of progesterone or other; and (b) is this generally a bad sign that AF will come? Any thoughts or comments gratefully received. xx