Small Problems lead to Big Problems? True

Well what started with a Simple injector replacement turned into a whole lot more,So i had this ticking noise coming from my truck, i clearly thought it was a exhaust leak, so when my truck stopped pulling right, i had a loss of power.i had a mechanic look at the truck and he crunk it up, floored it looked up the smoke stack and saw a lil puff of white smoke,and said it was a injector he didnt have the computer to let me know exactly which one and didnt wanna go thru pulling the cover off,Fast forward so i took it to a shop, put it on the computer and the mechanic went to cutting off each injector one by one, well injector #6 was faint,barely putting out you could hear the rattle, so i go back pull the cover off and shown nuff it was bad, not only was it bad, but the injector arm which has a roller on the edge started edging into my cam shaft, luckily i caught in time, that was the noise the rocker arm was apparently stuck and had a flat spot in it, im not sure if the baron inside the rocker was bad or what,but it feel like it seized up,compared to when i rolled the other ones with my hand,so it was affecting the injector.So i ordered the new rocker arm, getting some emory cloth to try and buff out the camshaft and bought a new injector, hopefully it will hold off long enuff till i get a new cam, but its not that bad i have the video but it wont post for some reason heres a pic of the bad rocker arm.it wont let me upload pic for some reason

Question is have any of you guys ever experienced this problem like this?
Thought the ticking was a exhaust leak,but in actuality it was a bad rocker arm on injector #6 with a flat spot rubbing against the camshaft,which leads to replacement of parts,JUST HAVENT BEEN MY WEEK,but hey this is the trucking business,So Shick happens i guess lol,gotta laugh at it,to keep yo sanity

 

Yep,dont know a company that takes em out and presses em back in,so i just ordered a new one.

 

What would be the cause of that Besides,i know the normal wear and tear but anything in particular,also would that damage the crank since it was wearing on one side?

 

The funny thing is when we found the extra problem,the mechanic thought i was mad,i said buddy this aint nothing,i got one thing on my side and that is this "TRUCK IS PAID FOR" LMAO My mechanic buddy argued me down and he believes the truck was like that when i bought it but thats hard to believe because when i bought it,it was over 3 years ago and i never had no problems with the truck besides the ac not working and a wore out airbag and cab airbag,this my 1st major issue with it,old but goody,truck,what i will be doing in the near future will be a overhaul top to bottom,ive allready priced some kits online between $2200-2500,i have a pre egr engine.the guy i bought it from said it supposedly had a rack job done a few years ago,i don't really believe that so the best way to know whats been done is do it myself,i priced my turbo also,thats $700,ill be getting things one by one and stocking em up,so when that time comes ill be ready,since this my 1st overhaul.

 

Ok will try and do

 

I keep getting file failed to open everytime i try n upload the pic, any body know whats the deal? Tryna upload from cellphone which is a droid