In reply to Jackspratt:
I think framing it as "just balls" or "just nerves" is misleading.
Clearly the issue you ran into was mental rather than physical, but there are a whole lot of mental skills involved in trad leading that you don't get to practice while indoor bouldering.
(Speaking as someone who does a lot of indoor bouldering.)
I know plenty of trad climbers who feel a bit rusty when they've just been leading indoors over the winter.
You don't mention whether you've been seconding or bouldering outdoors while you've not been leading, but if you haven't, then your ability to read the rock is also going to be rusty.
Saying it's "just balls" implies that you just need to "man the **** up" or some such cliche.
Whereas I suspect it'd help more to get more trad leading in, get some mileage in at more comfortable grades, and generally get your "trad head" back on *before* you start gunning for personal bests.