This question must precede "why-didnt-adam-ask-for-forgiveness".
A short recap of the events as I understand it: G-d asks Adam not to eat from the tree, Eve is brought to Adam to be his supporter, Eve decides to taste the forbidden fruit and shares it with Adam.
THen the Torah says something unclear regarding their response:
וַתִּפָּקַחְנָה עֵינֵי שְׁנֵיהֶם וַיֵּדְעוּ כִּי עֵירֻמִּם הֵם וַיִּתְפְּרוּ עֲלֵה תְאֵנָה וַיַּעֲשׂוּ לָהֶם חֲגֹרֹת׃
Then the eyes of both of them were opened and they perceived that they were naked etc.
Then when they meet G-d to explain what happened Adam simply recalls the event as it was without showing any sign of interpreting it as a sin.
So, Did Adam and Eve realize they sinned before they were severely punished?