Wanting to Sleep Over My Boyfriend's House?

I am 18 years old. Me and my boyfriend have been dating for two years. I approached my mom (still live with my parents) a week before the night I wanted to sleep over and told her "Mom, this Friday and Saturday I am off from work and I would like to sleep over *** house." That's all I said and my mom freaked the f*** out. Saying absolutely not, why would I ask her that, etc. I don't argue or anything and just walk away since she was obviously p*ssed.

I go into my room and five minutes later she comes into my room to yell at me even more. Among the things she says is "I don't like him, and he shouldn't want you to sleep over." "It isn't normal for someone to want that." She also said "Just because your 18 doesn't mean I don't have a say in what you do anymore." and "I'll pull the rug from under you real fast (threat)."

I am a good kid. I'm going to college, I was a A student in high school, I NEVER have done different from my parents answer on anything. There was a time a year ago of distrust (used to sneak out because my parents wouldn't let me do anything) but I've been honest with them ever since the incident. Also, I had full intentions of letting my mom know what I am doing stead of lying or just going out and saying "see ya!"

Advice would be wonderful. I'm leaning towards doing it because I have never stood up for myself when it comes to wanting to do something and my parents saying no because they don't like it. Even though it would cause tension, my mom can't do much anyways if I do decide to do it. But anyways, sorry for the ramble. I just wanted to see what the internet world suggests.
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I've been dating this guy for 2 YEARS. He was my best friend for over a year before we started dating.
Wanting to Sleep Over My Boyfriend's House?
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