Yes, Saudi Arabia has a right to be upset since the United States of America has been enabling and exacerbating the terrorism in which it its attempting to oppose. Hillary Clinton's comments are nothing but a political ploy in order to swing conservative voters to vote for her in the presidential election.
After being accused by Hilary Clinton of not doing enough to prevent its citizens from giving support to terrorist organizations, Saudi Arabia has a legitimate reason to be upset. Clinton, perhaps in her eagerness to show that she is willing to take a hard line with terrorist organizations and any who support them in her bid for the presidency, called for three of the U.S. allies in the middle east to do a better job of ensuring funding from those countries did not get into the hands of extremist organizations. This was perhaps not very well thought out seeing Saudi Arabia has also been the target of terrorist attacks and has been working to stop any support for terrorist groups.
Yes, Saudi Arabia has the right to be upset about recent comments from Hillary Clinton regarding the nation. The United States is a major country and power of most of the world, containing a military many times stronger than the next strongest nation. Other countries have the right to be upset over what goes on in the United States, as it could affect relations with their country as time goes on.
Every nation and leaders and peoples have a right to criticise the acts of others when they are seen to be counter productive to stability and peace. It is known that the Saudi regime has thrown a ton of money and effort at promoting a particular flavour of islam called Wahhabi. Wahhabi is a ridged interpretation of islam and is directly linked to the upsurge of ISIS and other extreme sects.
Saudi Arabia is upset over Hillary Clinton's recent remarks about their country, however it is not the time to be politically correct, and she in fact was correct about what she was saying. Saudi Arabia causes major conflicts and funds vile schemes in the Middle East and the world. Their ideology seems to be in opposition of the west, although they enslaved it with its' oil.