Pregnant

I'm 18 years old and I just found out that I'm pregnant. Me and my boyfriend have been tigger for about 7 months and we've been talking about kids but I never thought that this would happen so soon. I know I'm not ready for a baby. I'm still in high school and every time I bring up abortion he gets touchy about it but knows it's what we should do. I always knew that if I got pregnant before I graduated I would get an abortion but now that it's happening I keep thinking about what it would be like if I didn't. My mom was a teen mom with me and I know it was hard. She reminds me every day that she should've been safe. For that reason I can't tell her what's going on because I don't want to disappoint her. I talked to a girl I know that had an abortion and she told me that it's my body and I have to do what's best for me and I totally agree. I'm just scared of the pain and the fact that I have to hide it. If anyone has any advice please let me know I would greatly appreciate it.