Help with room treatment?



I know my set up is very modest compared to some on here but I am just getting into this over the last 4 or 5 months. I built a room specifically for listening and once completed my system has sounded so much worse. Bass is worse, highs are worse. I understand it is a fairly empty room right now. After addressing first reflection points will it get any better?
Or should I return to my living room?
Rega P1
Cambridge audio Azur 740a
Cambridge audio cp1
Dali Oberon 5’s

Room is 12.5 ft by 16.5 ft

Also not sure how to add a picture otherwise I would show you

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I'd imagine the rug is synthetic. But it does have a very nice under pad below it. And wall to wall wasnt an option, so I figured it would be better than the full out laminate lol
Don't forget about the "free" room treatments.  I recently further experimented with speaker placement and was amazed by the sonic improvement from moving them further out from the rear wall. 
Empty room??  wrong....   I have a very large room with 18 ft. ceilings.  I've been working with trying this and that....speaker placement, furniture, rugs/no rugs, pictures on walls, etc...  sometimes it sounds better, sometimes not....I keep the good and continue listening. Very hard to get it right.  I remember an Alpha Duetta sports car I had with 2 2bl carbs.....similar.