Birth control pills question for long time users!

Hi ladies! I'm a newbie to birth control pills so I have a few questions that maybe the long time users can help me with! When it's time for me to start a new pack is it okay if I change the time that I take them to a later time? The pack that I'm at right now that I decided to take the pills at a certain time is not convenient with my schedule from school. So when I start a new one can I switch the time to about 3 hours later than I usually take them in this pack? And another question, I've been taking my pills everyday at approximately the same time give or take 15mins, if I had sex today and my 7 days without pills is coming in a day, am I still protected or is there a chance I could get pregnant , I let my bf ejaculate inside of me today but didn't realize that in a day I start my 7 days without pills so I'm freaking out, so will I still be protected during these 7 days that I don't take the pill? Sorry this took so long to explain, hopefully someone could help me out! Thank you in advance!