US Mine Safety and Health Administration interview questions

The interview was very difficult due to the questions asked and I didn’t understand them enough to give correct answers. So therefore I believe I gave a horrible job interview.

Received call from Field Office Supv. for interview approx. 2.5 mos. after applying. 22 days later received an email from a HR rep. informing me I hadn't sent requested documents. After carefully looking at the email, I noticed that an initial request for documents was sent 12 days earlier, I never received the email. I immediately sent documents. Within a couple of hours received a tentative job offer pending me passing a physical and drug test. 1 day later received email from District office requesting info to set up drug tests and physical. 6 days later received email for drug test at a civilian clinic. 2 days later was instructed to set up pre-employment physical dates with Federal Occupational Health (FOH). 18 days later a nurse performed lung, hearing, vision, urine, and other tests. 16 days later a contracted doctor gave me a physical and reviewed and signed off on the test results of physical conducted by nurse. 16 days later received official offer of employment. The entire interview process, from initial contact by field office supervisor to official offer letter, it took 11 weeks.