Is it normal for me to feel uneasy and shaky while masturbating?

Hi. I am 18, and I masturbate on a daily basis. Whenever i masturbate, i feel like i am gojng to pass out. Ok, it is hard to explain without getting too into it, but i need to provide details, so here i go. I like to eub my clot a lot. I mean like a lot. It just brings me such a pleasurable feeling I can't even explain how amazing it makes me feel. I shake uncontrollably and it feels so good my eyes begin to drift shut. It is so good like, it makes my eyes forcw shut and i can't open them unless i stop. Another way i masturbate is in the shower, i let the water stream feom the shower head pound down on my clit till i feel a lot of pleasure. The same thing happens in the shower. I do not know if this is normal, because I know no one in person who does it. All of my friends shame anyone who does it and hate talking about sex even. They do not know I masturbate and I wish I could tell them without breaking a friendship. But anyways, I masturbate quite often, for maybe up to one hour and a half a day. I sometimes penetrate with objects, but it doesn't feel good, so I normally just rub my clit or g-spot. I love the pleasure that comes from masturbating, and never plan to stop, but how can I stop the feeling of my eyes being forced closed. I really feel like I will have a heart attack from excitement and that scares me. Whenever I rub my clit, I feel weak and uneasy, like it is controlling mg body. Please help. I am scared.