Weird motorcycle voltages

So I own a 97 Honda Shadow 600 vlx, 11,000 miles it's got some werid problems. So it's been misfiring when underlow rpm usually when going up a steep hill in to high of a gear or sometimes coming from a stop. Also one morning the headlights started to get really dim like it wasn't charging. My voltages are really werid too. At low idle the voltage reads 12.8v. At high idle with choke on the voltage reads 14.4v. If I rev it higher the voltage drops to 13.5v. Battery voltage reads 12.5v and battery voltage with key on reads 12.1v

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