Your boyfriend would not be getting pregnancy symptoms if you were pregnant- it is the woman that gets them. If you have had a negative pregnancy test
after your period then chances are you are
not pregnant.
To me, it sounds like boyfriend had some sort of bug or illness that was giving him those symptoms. Also, the symptoms you are describing do not sound like pregnancy symptoms that you get until towards the end of your pregnancy.
I would go back on thursday and get the test done and if you are not pregnant (and don't wish to be) .P.L.E.A.S.E use a condom and maybe the pill or another form of birth control as a back up method so your are double-protected.
Good luck and I hope you get the answer you want