Your first part is to get out of your prison. We’ll deal with the vampire later.
On the left against the wall is a GROWING SUPPLEMENT. Above it you can find an access hatch. Open the hatch to discover a SCREWDRIVER. A bit to the right is a small long light green object. It’s a LAMP. You can take this as well. In the middle of the room some leaves are growing. They seem to grow on some kind of MUD. Take that also.
Use the fertilizer on the small viney thing left of the door. That’ll make it grow and now you can use it as a ladder to reach the overide panel. Since you can’t open the panel with your bare hands, use the screwdriver to open it. Now to really override the system use the gob of mud from your inventory on the panel and it’ll shut off. Use the door to exit the room.
You have to reset the controls but the button doesn’t work. Only one way to proceed then: use the lamp on the alien and he’ll pass out. He happened to have your ammo. You now have a loaded weapon again.
You’ll walk further to the right, meeting the vampire. You’ll take care of him as well.
Game source: A copy of the game was found here on the internet.