Need some help!

Hi everyone! Stats: 5'7" SW: 198 CW: 185 GW: 145

When I started with CICO, I was consuming 1200-1500 cal per day and that was a comfy range for me. However, I recently started a marathon training program that has me running 3x per week, strength training 3x per week, and walking 10k-13k steps per day. I also have a job that has me moving throughout the day (I am an RBT in a clinic so I spend a lot of time chasing kids). On the previous calorie limit, I found i was ravenous, getting shaky, and experiencing headaches, so I bumped up my range to 1600-1800.

I've now been in a plateau for 3 weeks (weight has fluctuated +/- 1-3 lbs), which also coincides with the time i started the program. Did I jump up too high or do we think I'll be ok if I am patient and keep waiting for change?