Will my Wi-Fi improve with a secondary router acting as a repeater?

My room and the primary router are opposite sides of my house. At times my internet can be pretty good, but other times it's straight up trash. Today, I bought an ASUS RT-N12 Wireless Router as a secondary router for a wireless bridge. I just finished configuring everything, and have my new secondary router up and running in my room as a repeater. I did a speed test in my room for both routers on my iPad just to compare, and when I connect to my primary router, it has an internet speed of 11 mbps and my secondary a lower 8-9 mbps. My primary router is a D-Link dual band router (don't know much about routers), but it seems like a good quality router since my brother bought it for like $120. My internet has been really trash lately, at one point the speed was 0.92 mbps in my room, but now it seems to be back to normal.

Is my secondary router and wireless bridge pretty much useless since the secondary router is in my room, do I need to move it close to my router or something? Will my internet speed be a bit more consistent now that I have another router or should I just scrap the whole idea and get a refund?

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