Starving alllll the time.

I just started working out after.... erm 7 years of basically nothing. I always lived a fairly active lifestyle (bartender, server, walking/jogging with my dogs). In a year and a half I put on 25 pounds thanks to birth control and depression. I was rarely hungry and just ate for the sake of eating. After going vegan for a while I dropped 18lbs in 2 months and kept it off for 5 months without working out. I transitioned out of veganism and put 10 lbs back on almost 2 weeks later. Now, I went off birth control, I'm working out 6 days a week walking a loooot, eating healthy 1800 calories a day, but I'm starving constantly. Is this good or bad? Should I up my calories?