Slight cramps ☹️

I'm on Day 10 tomorrow and have obviously had negative OPKs since day 7 (slight line each day) and normally get a positive test on CD 13-15. I stopped AF on Tuesday and didn't BD until last night as my fella works away. I've had really slight crampy pains and a sore back tonight, I realise I'm not preg but does anyone get pains before ovulation or just for no apparent reason? I've never paid attention to my body as I've been on the pill for 10 years (have a 9 year old daughter) anyone any ideas on the slight pain I'm feeling? 🙄