Air Conditioner Question

Hello

i recently bought a 7,000 btu portable air conditioner for my room. exhaust hot air outside via 5ft tube and i sealed the room (there is only a door)

the room is built inside a room so you can say its air tight as i sealed the door with weather stripping.

now i did notice negative pressure but the ac temp wouldn't move below 78 degrees.

i opend the door a little and it dropped to 76.

now the question is this ac is not gonna do it just by the fact that i cant have the door open.

would a window unit be better for my room? and have it vent the hot air into the other room where i would have an inline fan bringing fresh air.

thanks

I see alot of guys use the window ac in that sort of set up.

bump.
Im trying to figure out what I should do in that same situation except I need it to be quite. 6x6x7

r scrubber is taking away all the air from the ac. you need more intake