Extruder heater disabled when print commences and ETA is -8 sec??

I recently went into repetier and tried to print something. I noticed that when it homes, it travels to its designated position and then extrudes a set mm of filament as I edited in the Gcode. Once it gets done, it disables the extruder and does not print.Also, before I even go to print, The estimated printing time is -8 sec? I have no idea what to check or what to look for because everything in my eyes seems correct.

What does "edited the gcode" mean? 8 secs sounds like it is just doing the moves you listed.
Did you slice a model and then edit the gcode ?
Look at the preview to see what the GCODE movements are - I suspect there is nothing.
The movements you describe are typicaly in the startup and shutdown code in both the host options and in the slicer. So with no model sliced that is all you will get if you save the gcode.
Attaching a file of the gcode will help us but I suspect its a fairly simple if fundamental issue.

When I put edited g code, I meant that I added a line of gcode in the startup to extrude a given amount of filament. I also added the M666 to offset my endstops since the bed is unlevel.

Here is my start up Gcode.
; Default start code
G28 ; Home extruder
M666 X-1.8 Y-.87 Z-3.3
G28
G1 Z15 F{Z_TRAVEL_SPEED}
M82 ; Extruder in absolute mode
; Activate all used extruder
{IF_EXT0}M104 T0 S{TEMP0}
G92 E0 ; Reset extruder position
; Wait for all used extruders to reach temperature
G1 E20 F100 ;extrude 20mm at 100mm/min



No the Gcode is already saved in the startup gcode. I Slice the model and then once that gcode is created, I dont touch it. I attached a copy of the Gcode

Im not sure I can help much but the GCODE comments are confusing as they don't have codes with them.
You have a M104 code to set the temperature but there is no M116 to wait for the temperature to be reached - even though the comment is there. Since you have extrusion I assume you preheated the extruder before running the code. I would change this for peace of mind.
I can't see anything in the code that should stop it after its turned the fan off.
Hopefully someone more knowledgeable will dive in.
I still think you are just running the start code and not the full file. Are you sure you don't have files with similar names or didn't actually load the file in to repetier when you went to print.