what rep range are you going for?
If you want to hit a bigger weight, just drop the reps a bit. You hit 20, then 3??? Shit bro, usually DC is a 12-20 rep range, you're hitting over that...time to move that weight up. maybe 275 on that incline? Maybe more? Rep range should look something like, 8-4-2, or 10-6-3 at the upper end. You're hitting 20, then only 3...that's because your weight was too low. You just did a widowmaker, and tried to turn it into a rp set. That's why you only hit 3.
Maybe it's time to think about cruising too. You may be starting to burn out. 13 then 2?? Usually the 2nd part of the rp set is about half the reps of the first part. I would consider cruising. When you do cruise, go back to IM and re-read all the stickies about 2-3 more times (I still pick something up, and I've read them like 10-20 times each!). And seriously consider doing the 2 way split.