Shake it off AZT. My coach always says that the workouts are not a magic recipe that cannot be tweaked (unless its' one of the "key TT efforts" he assigned last week). He praises me for bailing out when I get to the point of not being able to continue on with form. If you gave it your best effort then mission accomplished. Hydration could have played a big factor in your recovery between intervals, I doubt food would affect the short performance. Early in my core/resistance seasonal work "failure" was the goal when doing pull-ups, squats etc... For Z5/L6+ efforts that build strength you should not be leaving anything on the table when done and walking away when full is a good thing.

BTW, 3' intervals @ 370- 390 watts is a very hard interval. I hope you had 10' recovery between efforts.