There is a difference in what the British call "pants" and what Americans call "pants." You said, "he opened a hole on my pants because I didn't want him to see me naked," I assume the pants in that part of the sentence are your trousers? (Or are you talking about underpants?) Then you said "and he pushed his *** inside my vagina with my pants on," I assume that there, you are talking about your underpants? So, basically, the penis didn't go into any hole he "opened in your pants" except maybe into the fly of your jeans?
As Curfew says, if there is cloth between you, such ask he pushed his *** into you with your underpants still between you, it is extremely unlikely this got you pregnant. Also, do you know that you only ovulate once a month (and the egg only lives about a day?) If the event didn't happen on that day (or within a few days of it, because of how long sperm can live), you wouldn't have gotten pregnant because you had no egg waiting for the sperm.
Anxiety can do everything you are describing. You wouldn't have gotten pregnancy symptoms so soon from something that happened only 10 days ago anyway. When is your period due? Though being stressed can sometimes cause you not to have a period, my guess is that yours will come around the time you expect. Please try not to mess up your finals over this.
The only realistic way to achieve pregnancy is by inserting a penis into a vagina, directly, without the barrier of clothing or a condom. I understand that you are scared, but you didn't get pregnant from this event. Your symptoms really sound like symptoms of anxiety, but they are definitely not symptoms of pregnancy.
Here are some good resources to help you learn more about your body, and preventing pregnancy (and STDs):
https://www.iwannaknow.org/
https://www.plannedparenthood.org/learn/teens