There is no authentic Hadith about the virtue of looking at the Ka`bah, and simply looking at it is not an act of worship for which a person will be rewarded.

The period for which the pilgrim must stay in Mina after the day of Sacrifice is two days, namely the 11th and 12th of Dhul-Hijjah. However, the 13th of Dhul-Hijjah is optional and one is not obliged to spend it in Mina or stone the Jamarat; rather it is recommended only.

The one who is doing Hajj Tamattu` enters Ihram on the eighth day of Dhul-Hijjah from the place where he is staying. When he enters Ihram for Hajj, he does the same as he did when he entered Ihram for `Umrah, doing Ghusl and putting on perfume.

It is not essential to form a specific intention for Tawaf or Sa`i or any of the rituals of Hajj; rather the general intention is sufficient, namely the intention to perform Hajj or `Umrah when entering Ihram. Based on that, your Tawaf was valid and you do not have to do anything else.

If the interruption to take a break during tawaf was lengthy, such as an hour or two, then he must repeat tawaf and start all over again. But if the interruption was brief, there is nothing wrong with that.