Oh, no one commented on this. Sorry for the late response, but I'll throw out a few suggestions.
Double punctuation (such as "?!") isn't correct. I recommend just putting the question mark and letting the writing tip off the reader as to the tone. For example, "W-where am I?" "Where am I?" and "Where the hell am I?" all read differently. You don't need the exclamation point because of how dramatic the question is.
When you have a word restriction it's often best to leave descriptions as simple as possible while giving the full effect. Adverbs (words that modify a verb, usually ending in "ly") are often unnecessary or can be dropped if you use a stronger verb. This will save you precious words. For example, "silent and painfully careful" could be "silent and careful" without losing meaning. Of course, you could use a different word other than "careful" if you want to modify the meaning. Words like "cautious" or "meticulous" might get the idea across that you have to be careful to an unusual or uncomfortable level without adding a word.
I felt the plot was lacking a bit, which is understandable since you only had 100 words, but I would focus on a few different things to make the story more effective. One of these would be to get rid of the third to last paragraph about fear, and describing the feeling of being afraid rather than telling us "you are afraid." For example, perhaps you could say that we shiver but not from the cold, implying that we are shaking in fear.
On that same point, I felt the description of the cold was very vivid while the beast was very non-descriptive and ineffective. Maybe more details would help. Rather than saying the stories of the beast are scary, you could tell us one short story that makes us fear the beast. Perhaps it is best to omit the beast and focus on being cold but never finding shelter. I don't know what the goal was, but I'm not scared of the beast because it's too vague.