There must definitely be a reason for the call but the reason was at that moment he couldn't tell at least not till he would arrive.
Driving out through the secluded road he tries all he could to put his sanity in check, right there in his mind were the most thriving things he could think about everything ending with the thought of Antonia, in a way he thought himself silly for his antics.
A part of his mind told him it would have been better if he had just come off with the truth about how things were, still he wouldn't blame himself he thought he was doing what...