I was supposed to ovulate on Wednesday or Thursday if last week. If my chart is correct, I should be getting AF on August 18th. I stopped my birth control after my last cycle in July. Last cycle started July 21 and only last about 5 days. For the past 3 days I've been feeling off. Is it possible to have conceived?

Here are the symptoms I'm feeling:

Sore nipples (started Friday or Saturday, hasn't let up)

Random nausea (started Monday and it's off and on)

Random twinges or cramps/feeling of fullness.

Slight headache (started yesterday, under control)

More frequent urination

Heartburn and vey gassy (burping, etc)

I know it's early, but is it possible?