Not sure of your budget or how much they charge but you could try to see if Johnson Controls can help you. I would think that since your in webster you could get away with needing the room to be secure (with you in it) for maybe 30 minutes to an hour. Maybe put some steel plates or something in the walls so they couldnt simply go through wall. Ventalate to the roof since most likely they arent going to go there. Place a wireless IP camera (maybe trednet for example) in the room so you can view it remotely and get emails if someone goes in triggering the motion detection.
Now to get crazy, crazy cool lol. You could add sound insulation as well so they cant hear you talking to police on cell phone (maybe leave a charged cell phone in there, even an un activated one call 911). You could install ( try to imagine what I am trying to say here) multiple sets of the following: those security doors that only one side can be open at a time. You know the ones to pass things through in shady areas. If you know what I mean then the door that is on outside wall where instruders could be should open into itself so you could cover it up with a picture or something so no one would see it initially. Then from the inside you could put smoke grenades (legal as signaling device) in there and close your door and opening the outer one so they cant see also giving police advantage if they have to make tactical assault. Obviosuly wait for their command to do it lol. Yes you would have some smoke damage to your stuff but it could save your live and odds are you will never use it so its a non issue. Note the inner door prevent the smoke from getting in the room you are in.
Either way you have some time before your new child will be able to get to any firearms in a room with a closed door that have safety locks on the firearms.
Bullet proof glass to replace your window might be another option as well. As you see you can spend a lot of money. You can save a lot by doing it yourself as stated above.
