Hello, Thanks for your query. If the wound was caused by some dirty object, it is advisable to take an antibiotics. Moreover, in some cases tetanus vaccination is necessary. It is very hard to tell not seeing it. But smelly discharge from under the fingernail may be a sign of anaerobic bacterias infection especially, that under the fingernail there is a great environment for such bacterias. However infections under the fingernail are mostly very painful. The best way to find is to show it to the doctor as after a week such wound should be almost healed. I do hope that you have found something helpful and I will be glad to answer any further query. Take care