Is finding one or two fleas a big deal?

I had a flea jump onto me yesterday or what I believed to be a flea, so I went out got some shampoo and a good comb. I came back gave both my cats a bath, combed through them. I had found one flea on my older cat that looked rather large and nothing else on my youngest. Afterwards I applied their frontline which my dumb mistake for not keeping it up. I brushed my oldest again today and found a little bit of residue but no fleas. Their frontline works wonders to repeal the fleas but I am worried about my home. What can I do to keep my home clean and make sure fleas won't become a problem? If my dad finds out I even found one he will argue with me to get rid of my cats.