Does not having a Hajj permit, performing Ihram from Makkah on the Day of 'Arafah, and not spending the night in Mina invalidate Hajj?

Hajj is not invalidated by mistakes, but the pilgrim is required to offer a sacrifice (dam) due to leaving two obligations: entering into ihram from the miqat, and not spending the night in Mina during the days of Tashreeq.

The sacrifice (dam) is a sheep or one-seventh of a camel, to be slaughtered in Makkah and distributed among its poor.

An exception to the requirement of a sacrifice for not spending the night in Mina is for one who could not find a place to stay after making a diligent effort; in this case, no sacrifice is required of them.