Woohoo, I understand you and your girlfriend are young and afraid. My question would be
why did she put it back in? I mean the risks there are pretty obvious, right? She did do it knowingly... Maybe that is something you should talk to her about.
The chance that she has symptoms so early would be minimul. Could her bleeding have been her period? Sore boobs and many other symptoms can be the same as pms symptoms. So those don't always mean pregnancy. Her being sick, well, she could be just sick or terribly worried. Being worried about being pregnant has been known to cause pregnancy symptoms.
No one here can answer whether she is pregnant or not.
she needs to be tested! she can go to planned parenthood and get a pregnancy test (after she has been late for her period) or you can buy a pregnancy kit at the store.
Good luck! And relax.