Kbps/Mbps and MB/s and Kb/s is different. For every 1 Mbps, you can get about 128 kb/s transfer rate. 8 kbps = 1 kb/s
KB/s = Kilobyes per second
KBPS = Kilobits per second
For example, if you have a 15 Mbps down and 2 Mbps connection, you can get a max of 1.86 Mb/s and 250 kb/s theoretically.
The point is, Kbps does NOT equal to Kb/s. If your connection is running too slow, I suggest getting a faster service like Cable or Fiber or lower your upload speeds.
This is the same exact explanation that I have explained in this post
Another thing is that with DSL, depending how far you are from the central office, the speeds can go down if you far away from the central office.