Scarleteen

So I’m an 18 year old female, and I recently had unprotected sex with my boyfriend last month on the 21st. It was in the heat of the moment so we didn’t think about protection and he finished inside me. I took a plan b 30 minutes after but I’m kind of worried because last week I started bleeding but it was like black/brown and it was pretty heavy. It had stopped so I assumed it was a weird period but a couple days ago I started bleeding again but it was red thing this time but it quickly went to brown like the next day. It was extremely light. Both times I did cramp idk I’m just really scared that I’m pregnant. I want to take a test but I have extreme parents and I’m not able to get one.

Hello, welcome!
I’ll touch on your specific concerns below, but also recommend you read through this article: Pregnancy Scared?

Emergency contraception like Plan B, taken right away, is quite effective. It also can have side effects that affect your cycle, like heavy bleeding. Actually, to use the language on the Plan B website, side effects include “A period that’s lighter, heavier, early, or late.” So, while that is pretty vague, the takeaway I hope you get from this is that unusually heavy periods ARE a common side effect of EC, and NOT a common symptom of pregnancy.
The only way to know if you are pregnant is to take a test. Since you are a month out, a test would be very accurate at giving you that information. I am sorry that your parents are extreme- how were you able to access plan b? Is the person who helped you access also able to get you a test? Do you think seeing a negative result would calm down your anxiety?

My friends covered for me so I could spend time with my boyfriend, unfortunately he lives almost 2 hours away and Im not sure I’ll be allowed to go out for a while because of how they are. I’m having so much anxiety over this and other unrelated things so I’ve been really anxious and stressed to know if I am pregnant

I am really sorry you are in a place of so much stress and anxiety, and I can't imagine that not knowing when you'll be allowed freedom to leave your home is helping.
When you say you don't know if you'll be able to go out, does this mean any kind of leaving the house at all? Seeing specific friends? Your boyfriend?
Would you be able to go to see a doctor? What about visit a pharmacy, grocery store, library, community center?

I can tell you that it doesn't seem likely you are pregnant, given the EC and the periods. A pregnancy test can confirm that, we cannot.
My biggest concern here is the amount of restriction you are describing in your home as an adult.