Please help! What does early pregnancy feel like?

Jane • Engaged since 14/02/14
AF was due yesterday but I've had what I assume are pregnancy symptoms from practically the day after sex! Which would be 14-17 days ago! Been very bloated, had bigger, tender, achey boobs that have also had very sensitive nipples. Had nausea after eating, at times, headaches at times and fatigue. 
​Although at the same time, I do have chronic fatigue syndrome and irritable bowel syndrome.  AF is normally on time. Took test Sunday but BFN
​Can anyone offer any help please? 
​Thank you!