Front and back cramping after vasectomy

I've been back home for about 3 hours following a vasectomy today. After falling asleep on the couch I woke up being very uncomfortable. Cramping in my lower back and gut. No real pain to speak of in the incision area, just the 'cramping'. It almost feels like (please excuse the term) 'blue balls'.

Does anyone know if this is a normal side effect? Tweet