Restrict away!!!! :-)
Sit her down and tell her that you have noticed that she has been complaining a lot. It hurts your ears to have all the noise... so for 2 weeks... there will be no friends over... no overnights etc... You think that she just needs some relaxing time since you know she only complains when she is tired out... So she can get some good rest... :-)
Do not think that it will really change anything. She is 5. They complain and whine... And really she's just getting started. lol
Spend the next few weeks focusing on simple family fun.
Go swimming, go to the park, go fishing, go to the library, do arts and crafts, have her help in the yard, focus all your activities on the family together...
When my 8 yr old starts with the whiney pity me voice I tell her to fix it. I even have handed her a wrench, screwdriver, or what ever bob the builder tools her brothers have laying around... After about the millionth time of telling her to stop, fix it... I don't even have to say it... Just pick up a tool and hand it to her. I do make her close her eyes and breathe deep before starting again... It usually helps for a second or so... But she recognizes the emotion with the resulting tone of voice (If shes mad or has a harsh tone in her voice I tell her to stop... breathe,,,, fix the tone.... try again.)
My mantra also is patience is a virtue... Not that they know what a virtue truly is other than something good to have... Its funny to hear my 4 yr old tell his sister that "patience is a virtue"... Or my 8 yr old to say "dad, we have to have patience"...