Rick was seriously injured when his horse threw him...on top of a stick that pierced him in his side, the wound was not serious, and he managed to get off the stick.

During those hellish minutes he was having hallucinations about his people and those he lost due to the apocalypse, luckily he was found by a group of people, at least seven or eight people on there.

in his hallucination he heard the beautiful melody of a girl humming, in Rick's hallucination he was talking to his son Carl who died after being bitten by a walker, when Rick woke up he thought it was another hallucination, he was a little scared, worried and anxious.

"W-wait...where I am? T-this is not real...it is not real...!" Rick spoke anxiously, his voice made the humming stop, Rick realized that the person who was humming was the person who healed his wound.