Doubt of 1 week pragnancy & how to stop?

I have a 1% doubt that my gf is 7days pregnant, we had dry sex, not actual sex we are still virgin, I had released my semen in my underwear, semen has passes the underwear as well as my pajama, my pajama had wet in very small quantity(as I already mustarbate before 1days of the moment) , and my gf had also full dressed(under wear with pajama). I have doubt because 1. When I was checking my pajama it was wet (not that much wet so that my fingure will wet) and after the checking I did deep figuring, this is the main cause I m worring, and 2. Yesterday she felt vomiting and dizzy( head swing) , I was in worry but at last she told me that she didn't eat anything and doing household works that she was feeling, 1. Is it possible that she will pregnant, 2. If yes , what is right time to check the pregnancy, 3. If she is pregnant , what is duration of medication course to stop the pregnancy (how many times she need to eat medicines), 4. How much it cost ? (from now we will never do the same😢)