Can you overdo water changes?

[dramatic]

Also, don't forget to check your filter media. If it's clogged or old, it won't handle the bio load, and you'll get ammonia spikes. That'll stress your fish way more than water changes.

[oceanist]

True. And if you're using tap water, let it sit for a day or two to off-gas chlorine. Or just use a dechlorinator. Either way, your Tetras will thank you.