I know I've posted this numerous times before, but I'll just give you the definition now instead of a link.
Patriotism - one's love for a country that isn't restricted to blind love, one can argue and disagree with their country, and even see it worse than others, but can still be a patriot if that person still has love and loyalty to it
Nationalism - one's strict, biased, love towards one's country, and seeing their country as better than any other, never disagreeing or arguing against their nation