Strange ovulation! Opinions?

DH and I had unprotected sex on day 6 of my cycle. I've ALWAYS ovulated on day 14-16 but this cycle I ovulated on day 7. My body is evil! Lol (I have a 9 months old, a 2 year old and a 3 1/2 old.)

My question is how early can I test? And how early can I start having symptoms? I could very well be imaging this, but im urinating more often and exhausted. We really wanted to wait until our youngest was 2 to start tying again...

I didnt have symptoms with my children until about 6-8 weeks

Also, although this baby would be unplanned, it would be very loved, and plan b is NOT an option. So please dont suggest. Thank you.