False pregnancy symptoms?

Ashley
Some of you may think I'm crazy, but I'm hoping someone is experiencing the same thing cause that makes me feel better always! My son is 6 months old.
So for the past couple months I have been experiencing sore boobs randomly and random nausea.. My mind automatically goes to pregnancy but I have taken tests, all negative and gotten my period the past two months.. They've been weirder than normal but still red blood, by weird I mean not as heavy as I was used to before. 
I am on the pill and have been for 4 months now.. We are not trying what so ever. My doctor thinks maybe it's side effects because I even took a test at his office.
Any other moms have symptoms that could relate to pregnancy and convinced themselves they thought they were while totally freaked out? Maybe it's all in my head or my body is still getting back to normal.. I don't even remember what my body felt like before pregnancy. Is this normal or am I going crazy? Lol 
Thanks! :)