Just a useful point if not known, if you insert cotton wool after the oil, make sure you also put oil on the cotton wool otherwise what is in the ear will just be soaked up by the dry cotton wool making the oil ineffective. Not everyone thinks of this.
Re infection/abscess, I visited GP who thought my problem was wax and prescribed ear drops. Unfortunately there was an abscess which he had failed to notice and due to bank holiday weekend I ended up at A&E as the drops I had been prescribed shouldn't have been actually making the problem far worse, hence I was then treated with antibiotics.