Probably below happened.
By getting your SD card out you also got the battery out and this is a kind of soft reset.
And the date and time are set back to the date of the latest software update.
If you did not set your date and time setting to automatic your phone detects a difference in the real date and time and the date/time of your phone.
And your pin security sees this as a "attack" and locks the phone.
And there is basically no way to get in a locked phone then preforming a hard reset.
The only thing you can hope for is that you set your date time to automatic and that it may take a while before the network will set the correct time to your phone. I do not know how long this may take and if it will work.