First of all get a chalk and blackboard and write 100 times "I rode my bike on the road".
Anyway, I'm hoping your problem is fairly simple. The innermost chainring is mounted using different bolts than the larger pair. If you're lucky, you have some loose bolts on that chainring, and tightening with a 5mm hex key will solve it.
If you're not lucky, it could be anything (almost). One thing to consider is that using the innermost chainring means the highest chain tensions, so things like a bad bottom bracket bearing, loose right cup, axle deflection on the rear hub, and many other drive train issues will appear first with the granny (or any time you stand on the pedals).
Say a silent prayer and check the chainring bolts, otherwise you may be in for a long diagnostic haul.
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FB
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