Is it 'muddy' or 'mitch',
Welcome to the gab spot.
First, remove the magazine. (That little thing sticking down inside of the trigger guard in front of the trigger, push it up.)
Do you remember if you loaded a round? We will consider it (and all weapons) loaded.
If the safeties are 'ON', you can not open the bolt. Is the thumb safety on? Oh, yea, you said that one is blocked from being turned on/off. Is it pushed all the way forward?
Now look at the back of the bolt. There is a knob sticking out. Is it flush or on a shaft?
Play like the weapon is loaded. Finger/s away from the trigger. Pull that little knob back. If it clicks back only once (and some shaft was seen), the weapon is fully cocked. Now slowly open the bolt, keep you fingers out of the trigger guard.
Did this work?
Not being with you and watching, scares me.
The bolt has a 'half' cock position. You can also remove the bolt (open the bolt and flip the extractor up and slid the bolt out) and un-screw the extractor one turn and put the bolt back into the receiver. Don't expect to close the bolt, it can't. But it will foil anyone who doesn't know what they are doing.