If a person is cleansing najasat and it is the first water and both hands get wet with the same water, then the vessel of water should be grabbed with the same hands and the water should be taken with the same hands by dipping it in clean water. Water and even those vessels have become najis?

When water is poured once over the najis area, that area becomes paak and if you are using qaleel water, then only the water that seperates from the najis area is najis and not the area itself. Hence don't pay too much attention to these doubts.