came off my period on the 31st June and had sex that night and the following morning but he didn't ejaculate both times.
First, there is no "31st June", there are only 30 days in June. Assuming that's what you meant, t's highly unlikely if you had your actual period that you could have got pregnant that time (even if he ejaculated).
If you have a regular 28 day cycle:
Day 1 = when your period started (26/27/28 June?)
Day 14 = ovulation day (11th July ish)
Day 28 = period due (25th July ish)
then just under 2 weeks ago I had sex again where he did ejaculate.
2 weeks ago from today is roughly 2nd July. No where near ovulation and just a couple of weeks after your period finished.
the day after this I had a pink discharge (sorry a little gross!) which I have never had before and this lasted for about a day and a half on and off
Rough sex perhaps or your period hadn't completely finished seeing it was only a couple of days long and a couple of days after you had finished.
sex again about 3 days ago where he did ejaculate.
So about the 14th July. That could time with ovulation but is likely a little late
over the past few days I've been having dull aches in my ovary area, a bit of heartburn, feeling breathless really easily, very dark nipples (potentially from the sunbed but I not sure...), nipples are slightly sensitive and I've been ridiculously angry at times and could cry very easily.
I think you're probably ovulating late. Tomorrow would be about 3 weeks since your period started (or 21 days).
If you're showing symptoms then there's enough HCG in urine to make a test show positive.