Was my circuit victim of capacitor self-resonance?
There isn't much difference between the two (they are right on top of each other), however there is probably much more going on with the design. I'm willing to bet you have one of the following problems:



1) Your ground is not continuous and has large amounts of parasitic inductance  

2) Vcc has a large amount of parasitic inductance, or not enough local storage for the IC's with power filter caps.   

The problem is the things you can't see. On the schematic we commonly draw Vcc and ground as one net. When the circuit is built we connect ground and Vcc with conductors, these conductors have resistance and inductance (and between them capacitance). Usually when you have these wierd problems, it's because you have too much inductance, and you've built and RLC filter with the resistor being the load the C being a power filter cap and the L being a wire to the IC.

Make sure you use large conductors and avoid daisy chaining Vcc and ground. Each IC's current should have a direct pathway back to the power supply, otherwise you'll have common mode problem.

Another thing that could be going on is the voltage regulator could be improperly compensated, check the datasheet and make sure you have a proper filter capacitor on the regulator.