I sat up facing the wall and looked around, but there was nothing.
Literal
Wall [toward-に] facing body raise-and surroundings look-around-even nothing not-exist.
A narrative sentence chaining multiple actions: 壁に向かって体を起こし (sat up facing the wall) and 辺りを見回しても (even looking around) leads to 何もない (nothing). The ~ても creates a concessive: 'even though I looked around, nothing.' Vivid scene-setting, perhaps waking up disoriented.