Do you have another computer in your bedroom attached to the router?
If not, is there a telephone point somewhere between the lounge and your bedroom where you could connect the router?
If you can't move the router to a different room, can you move it within your bedroom? If you can raise it up (on top of a wardrobe?) or even move to towards the lounge, you may improve the signal. Even swivelling your chair round a bit in the lounge so your body isn't between the laptop and the router can help.
Otherwise, it would appear that the lounge is just too far from your bedroom.