Why does my body still go into shock and the thought of laying down beside someone freak me out ?

You might have been in a traumatic experience and your body and brain is still cautious around the things that happened before, even if you KNOW they will not do anything.

The only thing I'm able to think of for the first question is that it may be a panic attack. The second sounds like what are called "Intrusive thoughts." I don't see much information on this question.

It all depends on your mood. If your mood is good, you are in heaven and bad mood makes you feel uncomfortable like hell.

We are not certified to answer that question here at 7cups. I'd strongly suggest seeking professional help so they can help you out :)

You're too used to being alone. Let yourself thaw like a kitten adopted from abuse and you'll be fine in a few weeks' or months' time.

Every person have their own personal space and this varies from one another. One might be comfortable with skinship while others would love to remain in one metre radius away from everyone. This is normal and it depends on your own comfort with the other person in vicinity. It's normal. But it is not when it causes you too much discomfort that you have trouble breathing etc. When you say laying down beside someone, the first thought is that you are comfortable to be that close to them, but maybe you are freaking out because of factors that affect your comfort. Tell yourself that it's okay and talk to someone about it.

the traumatic experience maybe a person has experienced has produced a mental scar which creates discomfort or the thought of watching movies, hearing news, or stories about something bad about it can create this.

Perhaps this is because you have had a very bad experience in the past with another person. The trauma that you experienced is extremely powerful and if you have not achieved full closure from it, any reminder of the traumatic event may cause you to feel as you did then. Sometimes even just thinking about it brings back very bad memories associated with fear which can lead to tremendous anxiety. This can lead to avoiding anything that reminds you of that event for a very long time. Until the traumatic event is processed and worked on, probably with a qualified professional, it may be extremely difficult to move on. Please know that this is a natural process and no fault of your own. It takes time to recover from something like that.