Following surgery for pilonidal sinus
,there may be a bloody discharge for a day or two, but the discharge will then become yellow.Hence in your case you need not worry .Do regular dressing of wound , to prevent the condition coming back, you should attend the Out Patient clinic or your surgeon each week until the wound has healed.
You can wash the wound area as soon as the dressing has been removed. Soap and warm tap water are entirely adequate. Salted water is not necessary. You can shower or bathe as often as you want