LM324 for 10,000x gain?
The op-amp is configured as an inverter and, with +100uV on the input, the output will try to go negative but it can't because you restricted the negative power rail to 0V. So this means your source has to have a negative voltage fed to the input (a possible constraint).

The trouble with the LM324 is the input offset voltage is about 2mV i.e. about 20 times bigger than the signal and this may well be a positive offset and, as said above will force the op-amp output to go negative.

If it's a negative offset then 2mV x 10,000 = 20V and the op-amp is saturated hard against the positive rail (or as near as it can get to it i.e. about +3V).

Also, when running from a 5V supply, input bias currents could be as high as 500nA (across temperature). This will flow thru the 100 ohm input resistor and create an offset of 50uV - that's half your signal.

Stop this madness and use a proper op-amp suitable for the job like an ADA4528. It has input bias currents of &lt;1nA and an input offset voltage of about 4 uV. It is also a rail-to rail device on inputs and outputs.