Unwanted pregnancy. It cost in general?

My gf thinks that she is pregnant.. She has missed her periods by about 10 dayd now. She is showing hair loss signs, itchy skin etc. And she takes it all as a sign of pregnancy. We did have unprotected sex some 15 days ago so i myself am in a confused state. To be honest its a lot of stress. We tried the preganews pregnancy test kit today and it showed negative.. That leaves me in a for more confusing state. We agreed to do it 2 more times to see what the test kit shows.. Now my concern is that if it turns out positive. Is there any need of parents involvement if we want a MTP by pills. Both she and i are above 18. Is MTP by pills really effective? And if we go to do a MTP by pills how much will it cost in general? Please reply. Please reply, i am in a very wierd state and i want to find a solution for this. And for information not mine and nor her parents know about this case and we cant let them know too. So kindly provide the solution and answers based on this fact. Thanks.