I am a British passport holder traveling to New Delhi and then to Melbourne, my flights are with the same airline and my luggage will be checked into the other flight with the airline. I am worried because I do not have a visa and I travel in 3 days!
According to Timatic if you have a confirmed ticket you have Transit Without Visa:
Visa required, except for Passengers with an Overseas Citizen of India" card or booklet, or:
Visa required, except for Passengers with a "Person of Indian Origin" card, or:
TWOV (Transit Without Visa):
Visa required, except for Holders of confirmed onward tickets