Nephi certainly collapses time in this verse. It is quite unlikely that Lehi died immediately after pronouncing the blessings. To have occasioned the blessings it is certain that Lehi felt the end near, but was in sufficient strength of body and mind to pronounce those blessings. However, after that time Lehi "waxed old." His condition appears to have deteriorated, and some time later he died. Nephi gives us no information about the ceremonies of burial. They are nonessential to his purpose.
For Nephi, Lehi's death was not only the death of his father, but the death of his family as he had known it. With his father's death the glue that had held together a warring family was gone, and Nephi moves quickly in his narration to that part of the story.