Now this is what happened,
Yesterday I connected my Dell Inspiron 15R 5520 to internet via bluetooth via my Nokia X2-01. I usually get speed around 4-5 KBps but I was getting 20-30 KBps. I went to speedtest.net I got download speed of 0.23 Mbps (around 29 KBps). That is considerably fast for my bluetooth connection. I then went to network and sharing center and in the connection status my speed was 1Mbps. I took my SIM out and put it in my unlocked Airtel 3G dongle. I got download speed of 180-200 KBps. To get an idea of the situation I went to a nearby cybercafe where the guy uses BSNL EVDO Broadband but he was getting his usual 30-40 KBps. Today as well I was getting the same speed. So, today I took my uncle's BSNL SIM and checked but got the usual 20-30 KBps (in Airtel dongle).
Now, while I was writing this thread my internet got disconnected and when I connected back my speed went back to usual 30-40 KBps (in Airtel dongle). At first I thought TRAI must have done something but it turned out that it was just my SIM. What the hell is going on ???????????????? One more thing, its still showing my connection to be 1Mbps............