Is there a mdm hidden on my phone?Am I being monitored?

If you feel an unauthorized person/app is remotely using, controlling or monitoring your device, then that is possible only if you have done one or more of the following Don'ts...

1. Don't hand over an iPhone to kids or to a stranger without Enabling Guided Access
2. Don't share Apple IDs
3. Don't Jailbreak
4. Don't share sensitive information pertaining to your device
5. Don't give in to Phishing
6. Don't plug in your device in Airports and Public places through third-party cables and trust the device. Beware of Juice Jacking. (Especially in India)
7. Don't leave your iPhone unlocked and unattended in public places like offices, schools, malls, etc.

If one of the above is true then quickly change the Apple ID Password and Return iPhone settings to their defaults.

Contact your IT administrator or MDM provider to obtain the latest MDM profile.

1. Is this your corporate iPhone? Then please contact the system administrator of your corporate
2. If it is your personal device, in that case, do you have any profile installed by your corporate/organisation/enterprise/School Management?
   1. Erase the profile added by you If you have installed a profile on your own --> Install or remove configuration profiles on iPhone - Apple ...
   2. Or please contact the system administrator of the organisation who provided the profile to you
3. If you want to turn on SSL trust for that certificate, go to Settings > General > About > Certificate Trust Settings. Under "Enable full trust for root certificates," turn on trust for the certificate. Apple recommends deploying certificates via Apple Configurator or Mobile Device Management (MDM). --> Trust manually installed certificate profiles in iOS and iPadOS ...

A normal user like me does not want to know what these analytics/diagnostic data mean.

These are meant for diagnosis when the iPhone goes for service or repair at the Apple Authorised Service Center.

Check for Conflicting Apps: If the issue started recently after installing a new app, try uninstalling it and see if the problem persists.

While I wouldn't personally act on the Analytics report you provided, I encourage you to explore it for potential improvements. Taking this step is unlikely to have negative consequences and may boost your confidence. --> General Troubleshooting iPhone Issues: St… - Apple Community

This may help you --> Share analytics, diagnostics, and usage information with Apple

If you are experiencing some serious issue in the function of the iPhone then...

Take your device to an Apple Retail Store or Apple Authorized Service Provider, or contact Apple Support:

Apple Repair and Repair Status Check - Official Apple Support

Apple Authorized Service Provider

Find Locations - Location Selector - Apple

Contact Apple for support and service - Apple Support 

Alternatively, you may ...

Get a Genius Bar Reservation and Apple Support Options - Apple

Contact Genius Bar.

Manage Reservations - My Reservations - Apple

Profile options will exist, only if any profile is installed by your corporate / organisation/enterprise / School Management then please contact the system administrator of your corporate / organisation/enterprise / School Management

If you have installed any profile on your own --> Install or remove configuration profiles on iPhone - Apple ...

I have 4 devices none of them has any MDM or profile on my devices.

Some apps in the App Store will prompt you to install a profile using their App to get the full functionality.