Your Ticket is E Ticket so they will not allocate any coach number and berth number until the chart is prepared.
* Generally the Chart is prepared 4 hour’s before the departure of Train.
* for Morning or Late Night trains the Chart is prepared 1 day before till 9 P.M.
so check your PNR on 12 Feb 2013 around 9 P.M
you can SMS or call to 139 for PNR status
PNR <10 Digit PNR NO> to 139
or visit this link
When you booked your ticket its status was RAC 26. Now this is confirmed but the Coach/berth No. will be allotted during chart preparation. This will be done on 12/2/2013 at about 8 PM because Train No. 12262 Howrah-CSTM Duronto Express departs from Howrah at 08:20 Hrs. You cannot know this prior to chart preparation.
It was RAC earlier.
You can know the Berth number just 4 hours before the train starts.
give your PNR before 4 hours when the train starts.