Can I possibly be pregnant?!

Hello All,

Sorry for the long post.

I am currently ttc. My last lmp was Dec. 1st and only lasted 3 days which normally lasts 5 or 6. Spotted the day after AF ended and spotted the day after. 6 days after I have cramping on and off throughout the day. My ovulation day according to this app is December 16th my husband and I DTD on the 5th, 7th, 13th and 15th. I have been cramping on and off for the past 3 days. Today I woke up very dizzy and nauseated and have currently still feeling a bit nauseated. Had a dollar store test laying around and decided I would just test for fun and then I noticed a faint line on the test line followed by the control line. About 3-5 minutes later the faint line disappeared. Can I possibly be prego?