I ended up having unprotected sex with the man I wish to marry, although I didn’t want to

I ended up having sex with my boyfriend who I plan on marrying, but did not plan on having sex with before marriage. Now that this has happened, I am extremely upset and ashamed of my act aswell. Will God forgive me and help me get rid of this depression? Also, I pray I don't get pregnant. I am extremely depressed with what I have done and I cannot even seek forgiveness for my act seems like the worst I could have done!! Also, I don’t want to get pregnant and I pray to God to protect me and save me from all this.