i need help with my monostable circuit!!

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If that 555Ic can handle up to 200mA source/sink, then directly wired to the relay would be consuming up to 127.5mA at 9 volts, near its max capability, if that particular chip can handle that.
 
hmm, many have made those chips, some can be different current rating for what they can handle in terms of current, tho many are rated at 200mA max.
 
then the IC may be jammed on sinking, it may have been so the entire time, process of elimination for finding faults in any circuit unless directly known, is of coarse not simple.

The Source/Sink (Push/Pull) stage may be damage in the IC. Or the control stage for the internal switch may not be functioning correctly.
 
A monostable can accomplish this, I am in the process of acquiring some to control timing of Photo Triacs to switch AC.

Something is with that relay.
 
It's 3:20 A.M. I'm getting why did I not think of that moments....

The 555 IC does go High/Source when switched on, running on the resistor capacitor timer, the chip sinks at all other times (Off), when pin 3 is directly connected to the relay, the 555 IC will keep the relay on at all times, sinking the relay, and when the 555IC is switched on the relay is now getting positive at both poles, all tho not completely so, the 555IC does not fully supply rail voltage, the relay being a sensitive coil type by the datasheet for that model number can cause odd results with the IC.
 
No, no no trouble,

The relay, all be it a bit low for your voltage, the coil is rated again at 5V 70 -71 mA, and at again 9v it allows 127 agv mA, the coil can get rather warm with this,

to get the IC to drive that relay, the IC would have to be the power sender, meaning the pin 3 becomes the positive supply.

Pin 3 would need to be the relays positive, then the other end of the coil directly to the common GND to power supply, however the flyback diode now needs to be placed at the pin 3 to relay point then directly to the power supply positive.

Recap. 555IC pin 3 to relays chosen positive, relays chosen negative to main power common, flyback diode annode to the pin 3 relay connection, Cathode to the main supply positive.
 
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