Raspberries flower and fruit either on canes which grew last year, or the same year, and blackcurrants too tend to produce most of their fruit on new canes. This is why when pruning blackcurrants you take out the older wood and allow need shoots to develop on a roughly three year cycle.
Red currants, on the other hand, bear on shoots borne on older wood so should be far more sparingly pruned.
I'm wondering if you might have pruned your red currant in the same way you pruned your black currant and took out too much of the established wood?
If that's not the case, then it is quite possible that the red currant flowers were caught in a late frost. In general they are more difficult to fruit successfully than most other cane fruits.