6.9. Diesel wont start

I have a 6.9. Diesel that ran fine till when it droped about 9 degrees and I forgot to plug it in and it didnt start I recently replaced the alternator and I had my batteries tested today and one was dead so I had it replaced but now it just turns over and over and over and it never starts I checked to see if it might have got air in the lines I pressed in on the slot on my fuel filter and cranked the engine over and it shot diesel out imidiatly so that was rulled out I think the fuel pump works fine so I dont really know what it could be and I have tried ether and starting fluid and still nothing.

any help would be greatly appreciated. Thanks