@abuandrew virus infection on cellphone is becoming a big issue. You will need to address this the same way you would on any computer. Get a good antivirus program. Stop downloading apps if you do not know where they come from ;-)
Anyhow, I suggest that you check [https://www.malwarebytes.com/cybersecurity/basics/how-to-clean-your-phone-from-virus|on here] about how to remove any virus.
Since you are not sure if this is a virus, you want to make sure that you backup all of your files. Then remove those apps that are recent add-ons. After that, do a factory reset (it will delete all of your files. Make sure that you have a back-up of those) Also, make sure that you know your passwords. You will need those to sign back into your phone etc. If you do not have those, do not do a hard reset.