IP Profile for your line is - 3.21 Mbps
Well, that says that, at the mo', you'll won't get more that about 3 Megabits/sec download.
In your OP you meant to say "My speed is around 3Mb" ("B" means Bytes; you need small "b" to say bits).
However. need your full router stats to say whether you should be getting more.
If using the BrightBox: Advanced Settings/ Accept/ System/ ADSL Status.
What was the estimate EE gave you on signing up? And also from here: BT BROADBAND AVAILABILITY CHECKER
1999: Freeserve 48K Dial-Up => 2005: Wanadoo 1 Meg BB => 2007: Orange 2 Meg BB => 2008: Orange 8 Meg LLU => 2010: Orange 16 Meg LLU => 2011: Orange 20 Meg WBC