It is OK to take an antidepressant and a thyroid medicine together so long as your doctor has written prescriptions for them. It is possible that a low thyroid could be responsible for some of your...
Your doctor should have advised you on this matter when he prescribed those. You may call his/her office to find out. Or you may contact a local pharmacy.
Yes, this would be OK. Remember that Percocet is very addictive. Take it exactly as your doctor prescribed and don't take extra. Don't take other pain medicine on top of this.