Anyone, expert or beginner, can give an overdose of any drug, either to an animal or to a human being.
There has to be a first time for any owner to give their pig a drug. 2 drops can be given from an eye dropper and, if only 2 drops are put into it, there can be no risk of an overdose. If needs be, practise giving the pig 2 drops of water until you have gained confidence in your ability.