Hey there IsaiahBlair,
Thanks for reaching out to Apple Support Communities. I understand you’re hearing an alert from your iPhone but not able to identify what it’s related to. I’ll be happy to help.
When the alert goes off, you’re not seeing any visual notifications on the screen at all? No badges appear on any apps? If not, go to Settings > Sounds & Haptics and look under ‘Sounds and vibration patterns.’ You may be able to identify what is using the chirp or whistling there. If not, go to Settings > Notifications. Apps that use sounds for alerts will be listed here. You may also be able to identify which app is causing this here as well. You can read more about this here:
Use tones and ringtones with your iPhone, iPad, or iPod touch
Let me know if this helps.