Yes you can get pregnant while using a condom due to the condom being reused, has a hole(s) or burst without you knowing. To decrease this chances buy your own condoms and place them on yourself, and if it's in your head, talk to someone and buy a pregnancy test.
NO you cannot
If you're not taking the pill, it's always possible to get pregnant, fake symptoms or not.
You can experience PMS symptoms and be pregnant yes. But if you get your period then you aren't pregnant.
Even in the presence of bleeding, you could still be pregnant.
Yes, condoms are not 100% effective. Read the label on the box.
Yes, if it leaked inside the vagina you could get pregnant. Using condoms with spermicide will cut some of this risk.
YES.
yes,you still COULD be pregnant. Not every woman has the same symptoms but nausea and tiredness are most definitely symptoms.
There is a high possibility, however you should always use condoms and practice safe sex. You could get STDs, crabs, AIDS, etc.
pregnant?
Not unless you had no barrier when you ejaculated into her. If you had the condom on and ejaculated into the condom while you were inside of her, then exited her and changed condoms (unless the condom broke) you could not get her pregnant. The only way for her to get pregnant is if you ejaculated into her or emptied your fluids into her (and most condoms have spermicide). If neither are the case, it is nearly 0% chance that she could get pregnant.
yes you could be pregnant.