Did you put in something for lubrication holes or grooves or something into the rod ends? usually they have a small hole on both ends on the crankshaft side to help feed oil into the rod. Yes the little end of the rod can get quite a bit of abuse when the engine is running, as it is near the piston and all the heat and it doesn't rotate all that much either. So it needs a little extra help. I like to look at what some of the successful engine designs do for the connecting rod and use those ideas or techniques myself when I make a rod too.