kal shab-e hijraa;N thii lab pah naalah biimaaraanah thaa
shaam se taa .sub;h-dam baalii;N pah sar yak-jaa nah thaa
1) last night was the night of separation; on the lip, the lament was sick-ish
2) from evening to the crack of dawn, on the pillow the head was not in one place
In the second line, to depict the mood of restlessness he's used a very fine image. In the whole verse the style of realism is dominant. If there was lamentation, then it was in a weak voice, like that of sick people; and if there was head-beating, then instead of the exaggerated mood of beating the head against the wall, he sometimes turned his head this way, sometimes that way, on the pillow.
If it's considered in a traditional style, then it seems that he's made plain the condition of weakness. But not from a single word does a straightforward reference to weakness emerge. The 'implications' are very fine.