sometimes I say the word "jesus" when I'm shocked or tired because I've seen a tv show or a youtuber say it and I don't really think when I'm saying it, I've only questioned it recently.
so, am i a kaffir and should perform ghusl because i replaced calling for god with jesus, or should I just watch my mouth?!
Taking the name of Prophet Isa () or Jesus in vain is something that the Christians do. We as Muslims are commanded not to imitate disbelievers and warning for one who does so is very strict.
Narrated Abdullah ibn Umar:
The Prophet (ﷺ) said: He who copies any people is one of them.
According to this fatwa, this Hadith implies that it is at the very least haram to imitate the kuffar, although the apparent meaning seems to imply that such a person is a kafir.
Nonetheless, it is quite clear from the above that what you're doing is wrong and sinful. You must stop watching TV shows or YouTubers who are leading you to behave like this. It is obligatory for a Muslim to stop an evil, even by the least of means if all other means are inviable.
It is narrated on the authority of Tariq b. Shihab:
It was Marwan who initiated (the practice) of delivering khutbah (address) before the prayer on the 'Id day. A man stood up and said: Prayer should precede khutbah. He (Marwan) remarked, This (practice) has been done away with. Upon this Abu Sa'id remarked: This man has performed (his duty) laid on him. I heard the Messenger of Allah as saying: He who amongst you sees something abominable should modify it with the help of his hand; and if he has not strength enough to do it, then he should do it with his tongue, and if he has not strength enough to do it, (even) then he should (abhor it) from his heart, and that is the least of faith.
I think it depends on your philosophy. As long as you don't take Jesus as a Son of God, or as a God, then you are safe.
Allah knows Best.
