Making healthy choices

I am 20 weeks pregnant!!! Yay halfway! With my first pregnancy I kept up a running and walking regiment (finished a marathon 2 months prior), ate very healthy and felt great. I lived in Hawaii so with longer days in the winter and being a FTM I found this easy to do. With this pregnancy heat and morning sickness stopped me from running during my 1st trimester. I have mainly eaten carbs and fruit. I have upped my veggie intake ever since feeling less nauseous but am struggling to keep any semblance of a walking or workout routine. I am a part-time elementary art teacher and online English teacher in the early morning and evenings. I have a 4 year old and a husband who works late. My only time to workout is directly after I eat lunch before picking up my daughter. I am so exhausted and lazy mid day. Now I am faced with winter and shorter days on the east coast. I am also craving sweets like anything with chocolate and white sugar in it. This is unlike me. I like to workout in the morning but my teaching schedule doesn’t allow for that unless I wake up at 4am and I can’t quit because honestly we need the money. I know I need to exercise! I feel so unhealthy. I need help, energy and motivation. I would love to swim but can’t afford a pool or gym membership and am new to my area so don’t have a lot of friends or any family around for a workout buddy. It is definitely getting me down. Any suggestions or motivations would be greatly appreciated. Thank you for letting me vent and post my problems. I should also mention doing everything right the first pregnancy led to being induced 9 days after DD because of too much fluid around baby then a 56 hour labor that wouldn’t progress after 8cm dilated and an emergency cesarean... so working out for an easier labor is not much of a motivation.