If I voted 30 times in a day and forgot to which questions/answers I have voted.
How can I find my recent votes cast?
Unfortunately, you can't. There is nothing in the interface that lists the posts you voted on, just the total vote counts per week, month and all time.
See Can I see my vote history on the main meta.
The above now obsolete information: As of 2012-04-26, there is now a Votes tab in your user profile (source).
You'll find your voting activity there, along with close/reopen and delete/undelete vote history. This is only visible to yourself, others don't see that information in your profile.