No, do not kick the door down.
You're in an unfamiliar area, in what appears to be something of a dumping ground for bodies.
The fact you believe you can kick down the door or open it, yet these people apparently did not do the same suggests that there's more to this than simple popping the door open and walking off.
Check the bodies as best you're able for anything usable, weapons, tools - even a swiss army knife's better than nothing.
It may be nauseating, but your primary concern here's suvival and gathering information to make said survival possible until you've got a better picture of what's going on here.
Listen at the door, control your breathing, keep quiet and see if you can pick up anything that would suggest you're not alone.
Do NOT put your hand through any opening you haven't checked yourself first.
Poke something else through it, wiggle it about cautiously, see if there's any traps.
Try and find something else ideally to poke through to open the door, be quiet, if the hinges suggest that it opens inward, brace yourself against it incase somebody attempts to kick it open, if it opens outwards, be ready to get out the way if it's swung open.
If possible, keep as much of a wall between your body and the outside as you can, not the door.
Until you're aware of what's going on, how much danger you're in, needless risks are going to get you into trouble.