No, you can't. In the past, there was no Prettiest Profile Contest Emblem, so the Moderators would grant the winner a Profile Designer Emblem instead. Nowadays, with the former being the official Emblem for the Prettiest Profile Contest, the latter is only granted when a Staff member is appealed by one's profile designing.
Someday, you might get it, Vikalp. :] Unfortunately, you cannot participate in April's Prettiest Profile Contest.
BTW, can't I take part in April's Prettiest profile contest? The rules(Jordan's post) clearly state that previous winners CANNOT enter. BUT the member who only have the profile 'designer emblem' and not the 'prettiest profile contest' winner CAN enter. That's so unfair! I want to get the profile designer. I even asked netto about it. But he...he just told me to join PPC. What should I do? ;~;