Baby weight

I'm 5'4 and I'm 21. I've had both my kiddos back to back. I was 213 when I had my son (my youngest). I lost about 20lbs after having him. I gained it back, I was 207 then I started working out, and got down to 201 but it stayed there for about a month. I gained about 4 lbs from my vacation last week. But I got sick yesterday morning and I'm at 200. How do I get on a good track with losing this baby weight? My son is currently 7months. He was born in January.