Nutty historical linguistic fact of the day: the -α of the first aorist and -ν of the second aorist first person singulars are both reflexes of the same ending, *-ṃ, which yields -α after a consonant but -ν after a vowel (cf. Gk. neut. sg. -ον vs Lat. -um).

Even more fun: this *ṃ corresponds with the athematic 1st singular-μι, just without the -ι, which marks the present. The same relationship is visible in secondary 2 sg. -ς (ἔ-βη-ς) against athematic primary -σι (δί-δω-σι).

It's there in the 3 pl. too. Primary -ουσι goes back to *o-nti (cf. Doric -οντι, Lat. -unt), while secondary -ον goes back to *o-nt, with typical loss of the final stop. So 1 sg. and 3 pl. in the second aorist aren't really the same, they just look it.

(Latin loses all final vowels [ἐστί = est], so this distinction is completely lost: amas, amavis; amat, amavit.)