Living on the earth is convenient as the atmosphere protects you from UV rays, where the temperatures are regulated, and the atmospheric pressure is well maintained. This is, however not the case with being in space without a space suit as the atmosphere is more hostile.
Here is what would happen if you found yourself in this situation
Lack of oxygen
You will lack oxygen15 minutes of being in space without a spacesuit. As a result, your body will swell up, get burning sensations, and suffer from mutation. You will also pass out and the lungs will most likely explode.
You will suffer from ebullism
Due to a reduced ambient pressure, bubbles will form in your body fluid. The low pressure in space will lower the boiling point of your body fluids to 37 degrees which will lead to the formation of bubbles. These bubbles are what will lead to the swelling of your body where you may be twice your normal size.
You will experience a brain drain
Due to the lack of oxygen, your brain will go into a shutdown mode and this will lead to loss of consciousness. You will survive this if you get help in 2 minutes but if this extends longer than this, it will be too late.
You will not explode
Human skin is strong enough to ensure that your inner organs will never spill over despite being exposed to intense pressure. The skin will also ensure that your blood remains high enough such that it will not boil.
If you are rescued within two minutes of being in space without a spacesuit, you will survive the ordeal. If this time lapses, you will die.
To stand a better chance of survival in space, never hold your breath as this may lead to rupturing of your lungs. Keep breathing normally and who know… help may arrive on time and you live to tell the story.