Your phone's internal storage is encrypted so remotely accessing the data stored on it isn't just as simple as connecting a USB cable. Even for you to access your own data on your phone, that's integrated with the lock screen. The encryption key is stored within one of the system-level partitions in the internal storage. So the data is protected by the encryption, and when you use your lock screen that unlocks the key. Just offhand, it doesn't sound like your phone was compromised.
But just for your own peace of mind, follow rvbfan's advice, reset the passwords on your all your social media accounts. If you have a relatively long history online and you don't reset your passwords at least every few years it's a good practice to change them anyway.
You should use the 'Have I Been Pwned' website to check your email address(es):
Have I Been Pwned allows you to search across multiple data breaches to see if your email address or phone number has been compromised.
haveibeenpwned.com
It may seem like a big risk to voluntarily post your email address there, but the site has a solid reputation with a history going back several years. The site has a very extensive database of online breaches and vulnerabilities, and it will scan an email address for any matches. This is a useful service, not necessarily even related to what happened with your phone recently.
You should also take the proactive steps to freeze your credit. It's a good practice to protect your credit score.
A credit freeze can help protect against identity theft. Learn how to freeze and unfreeze your credit reports.
www.investopedia.com
Data brokers are now a profitable and nasty problem, you might also want to check for your online presence even further (this can be an involved, time-consuming project)
How to get off of people search sites like Pipl, Spokeo, and WhitePages.
www.vice.com