As smiley piercing mostly a piercing is described, which sits in the labial frenulum that connects the upper lip in the middle with the gingiva.
Because the labial frenulum is very thin and consists of mucosal tissue mostly there are no complications during the healing. But you should waive on alcohol, tobacco, hot and acidic foods especially while the first days and also use a douche to burble regularly.
Then the healing takes about 2 to 3 weeks.