Really unlikely you'd have conceived on the last day of your cycle. So... are you also charting your BBT (basal body temp) and mucous? Or just writing down the day your period starts? Charting is generally considered temping, etc.
Your symptoms started way too early to be considered pregnancy symptoms. In fact, it appears your symptoms started when you should have been ovulating. A woman's first symptom is usually a missed period, followed by the other symptoms.
Sounds like you are stressed out. Why are you having unprotected sex? Do you want to be pregnant?