Thank you for reaching out to the EmpowHER community and for sharing your question!
Reading through your post, I am sure you are quite confused and really stressed out about all the things going on with your body!
It sounds to me that you are experiencing breakthrough bleeding and your body is adjusting to the pill. I can't tell you over the Internet if you are in fact pregnant, but missing a pill and changing the times decreases the effectiveness of the level of protection.
The light pink spotting does sound like implantation bleeding, but the only way to know for sure is to take a home pregnancy test.
I wish I could tell you a better answer, but there's always risks associated with unprotected sex.
Headaches, dizziness and a runny nose could be a 24 hour flu bug and not always pregnancy symptoms.
I hope everything works out. Will you take a pregnancy test to rule it out?