Opk Help?

Lauren • Married. Me - 21 Him - 24 TTC #1 since 12/14
So this is our 4th cycle ttc but our first using opks. I'm really confused. I'm pretty certain i have gotten positives 4 days in a row. I'm 20 years old and Im pretty healthy. Is my body just lagging to ovulate? I stopped taking birth control in October but i have been having regular AF since November. Is there a possibility I am not ovulating at all since there is such a long surge? Maybe it's time to go see a doctor? I'm posting the picture of all four test. They are in chronological order of testing day. I guess I'm just freaked out that something is wrong with me. Any advice would really be appreciated.