I am delighted that you were intrigued, have read up on the subject and have decided what is best for you, and from the weight you said you have lost you must be pleased.
As you will have noticed your cod liver oil is giving you about 2 grams a day of DHA which was suggested by a trial to be the level at which take up drops off in women.
As to olive oil it is essential it is a virgin olive oil (preferably in a darkened glass bottle)as processed oil is likely to be much higher in omega six 50%. I am not sure how the omega nine in olive oil interacts with the elongation pathways of three and six, but several trials suggest significant benefit for BC. On a less is more basis I try and use a desert spoon a day as a dressing for salads etc., but I am afraid it is no more than a guess as I have not seen any specific trials as to the optimum intake.
Here is an article on olive oil
http://www.living-foods.com/articles/oliveoil.html
RB