Missed period last month with possible pregnancy symptoms but now I'm on my period?

I missed my November period completely last month. I've had fatigue, breast sensitivity, headaches, and pretty much everything except food cravings. In fact it's the opposite. I have to force myself to eat. Also, I have craved alcohol lately which is abnormal for me because I pretty much only have the occasional wine with my parents. I have had a mild run in with Anorexia so I was used to missing periods. I also exercised a lot which facilitated the absence of my monthly gift. I recovered and met my boyfriend and only sexual partner of over a year. We always use protection. We even started using a condom with spermicide in it a month ago. I am also on the pill and have been for about a year before having sex for the first time. Yesterday I got my Christmas gift from Mother Nature and it started as brown discharge. I was hoping it was only old blood but I saw implantation bleeding is a cause for the symptom. I was further worried when I had most all of the pregnancy symptoms. I'm So confused about what is going on with my body. Today seen a bit of brighter red blood. I've heard that you can still get your period when pregnant. The last time I had sex was the 21st, 4 days before the first sign of brown discharge. I am 20 years old and I cannot have a baby. Also, having a baby inside of me is my number one fear in this life. It reminds me of Alien. I am diagnosed with depression and anxiety along side mild ADD. I am on medication for all of it but I left my take as needed anxiety pills at home while I am staying with my parents for the holidays. I'm am having panic attacks and trouble sleeping. My parents do not officially know I have sex and I will not let them find out. Please help shed some light on what my symptoms my indicate. Will I be able to trust a home pregnancy test?