The series is not yet over and three test matches remain. If Indians get overconfident, then they will end up losing the series. The weather seems to be improved in England and it won't be impossible for the hosts to win the series by a margin of 2-1 or 3-1. And trust me, this has happened to the Indians manytimes before. And apart from Rahul and Rohit, none of the Indian batsmen are in good form. The victory in the second match temporarily took the focus away from the poor form of Pujara, Rahane, Kohli and Pant.
2 weeks so plenty of time for both teams to think about next game and i doubt Indian team will be over confident, Indian fans? Yes!! And i agree there is always possibility of India losing series but its also true for England, in hypothetical scenario both teams has 50-50%. England has a home advantage but Indians are playing as a team and everyone is contributing for the team's cause, this is missing from the English team and Jimmy-Root are only 2 players who dragging their team, Root is in his career's best form atm.
England's squad for the 3rd test
IN - Dawid Malan (Batter), Saqib Mahmood (Seam bowler)
OUT - Zak Crawley, Dom Sibley, Jack Leach