First question: Are your drawings haram?
I have recently studied many online fatwas on this subject.
Fatwas are not unanimous on what is allowed.
As I do not know, what parts of the people you have drawn, I cannot decide whether it is permissible according to all interpretations
Most strict interpretations say you must not draw portraits and whole bodies, maybe the outline. Drawings of parts of the body for medical or scientific purposes are allowed.
There are also less strict interpretations who do not see a mere drawing as an animate picture, see here and there.
Shia Islam does not prohibit drawings of humans at all (except drawings showing nudity or are haram for an other reason).
If they are haram (according to whose point you trust): What should you do with them?
You can throw them away.
What should you do to be forgiven?
You did not commit a sin that can't be forgiven.
You repent and ask Allah for forgiveness. It is said that we should do that by the time of your fajr prayer. You can say
My Lord! Indeed I have faith. So forgive me my sins, and save me from
the punishment of the Fire.
Because it is written:
And those who when they commit an indecency or do injustice to their
souls remember Allah and ask forgiveness for their faults; and who
forgives the faults but Allah. And (who) do not knowingly persist in
what they have done. (As for) these their reward is forgiveness from
their Lord, and gardens beneath which rivers flow, to abide in them,
and excellent is the reward of the labourers (3:135-136)
Allah is the most merciful.