I had my wisdom teeth out about 4 months ago, i ended up getting dry socket, you will know because when you have dry socket you will have an awful headache that will NOT go away, you will feel like you need to lay down in a dark room with no noise what so ever, your head will throb and you will feel shooting pains in your jaw.
First sign is usually a bad smell or really bad taste in your mouth. Severe pain also follows. If you suspect that it is dry socket see your dentist ASAP.