Acting up

Deliberately behaving in a difficult, obstinate, aggressive or provocative manner.

Typically results in harm to and/or conflict with other individuals.

"Dear Mr. President, tell me what to do
These niggaz acting up in the hood, send mo' troops" (Tupac)

hold up

wait a minute! postpone your plans, there's something that must be addressed immediately

hold up, let me grab some munchies before we get goin

Clam Up

To suddenly keep unusually quiet, often in regards to the divulging of information.

Carol clammed up about the incident at the bakery, so we never did find out whatever happened to Nate.

cock-up

A shambles. Sounds vulgar, but may not be; it may be a grouse shooting term. Customarily, shooters employ beaters to disturb birds on the ground and drive them into the air towards the guns. Normally one only shoots grouse hens, so if the beaters were by mistake to put up a grouse cock, they would warn the guns not to shoot by shouting "Don't shoot! It's a cock up!"

Can also be a transitive and intransitive verb.

One's whole shoot today was a disaster - one cock up after another. Now where's Camilla, the slapper? One feels like giving her a Dirty Sanchez. - Prince Charles

Another day, another cock-up - Tony Blair on the Iraq situation

The whole Iraq situation has cocked up badly - Tony Blair on the Iraq situation

I really cocked up Iraq, didn't I? - Tony Blair on the Iraq situation

bugger it up

break it, ruin it, spoil it or damage it in some way

Don't lend him anything of value. He'll just bugger it up. He's got the Shitters Touch.

fibed up

Combination of being fired up by the good vibes of a particular situation.

This convo has got me all fibed up.

Time's up

A reckoning. Face the music. You're going to get what you deserve

Time's up. The end's in sight and you better face the consequences of your deeds