Can anyone help my puttering dd15

can anyone tell me what is wrong with my DD 15 I'm currently on a run it's a 2 drop I was able to make it to my first one but when I was done getting unloaded I put it in low gear and accelerated she took off like normal but as I started to gain a little more speed the accelerated it started doing the exact opposite and started slowing down . Everytime I try to accelerate it would rev up while in gear so it was kind of pick up speed but then it would slow down like it would completely lose power for 5 seconds or so then it would rev up again and It would gain a little more speed but then lose acceleration power and that's all she did I couldn't even get it no more than 3 gear the whole time I had the pedal all the way down. I have three lights two check engine lights and one red. She gave me a few codes eec61 SPN 3361 and another spn5246 eec 6 1 can anyone tell me what is going on with the truck I have heard that you could be the doser valve or a sensor of the DPF when are you guys can just give me an idea where I could possibly look 2 at least get her going I would be very grateful

 

Your right i towed to freightliner they found that the splash guard behinde the one box had kinda cut through a wire. They changed the wires and got me goin agin..but 20 miles down the road truck was running like it should. I was doin a steady 70mph and like a flip of a switch check engine and the other ML light and the red stop light came on agin. 70mph droped to 10mph, i managed to pull over. Now im at the same issue i had before i got towed to freightliner. But now the codes are the same eec 61 spn5426 for all 3 alarms, except now FMI 15,16,17

 

So by any chance would you happen to know how i could possibly make the truck do a parked (force)regen? Or maybe clear the governing codes. I heard 3 start cycles and starting it on fourth might work..OR do i have to have a computer hooked up to it and tell it to regen?..

 

So is there any steps i can do to make it regen? Or leaving it on for 40 minutes should do it?