No, it is not a conjunction. The word cramped is a verb, or adjective. It is the past tense and past participle of the verb "to cramp" (to spasm, or to restrict), and as an adjective may mean either painfully contracted (e.g. a muscle), or restrictive in space or comfort.
Since cramped is only one syllables, it would be cramped.
The opposite of cramped (space) is spacious, roomy, or open. The opposite of cramped (tense, tight, contracted) is relaxed.
It was very cramped in the elevator (lift)
The word cramped is a regular verb. It can also be an adjective to describe something that is restricted in size.
Would be hard to travel in a cramped car because it is uncomfortable
Yes,it is. Cramped is the past participle of the verb "to cramp" but usually means overcrowded (which would cramp your movements). It could also mean aching from use, as in cramped muscles.
In conjunction with
Contracté
Cramped
"Cramped" and "crammed" both refer to a lack of space or feeling crowded, but "cramped" typically describes a physical feeling, while "crammed" can also describe a situation where something is filled tightly or to capacity.
squished
spaced