Bedbug bites or breakthrough chickenpox?

So my oldest daughter is almost 5. About 2 weeks ago she started to get what I thought were mosquito bites. However it is winter and I haven't seen any mosquitos. New bites kept popping up. I did some research and decided she had bedbugs. I have kept her out of her room, washed all bedding, sprayed down everything. I never once saw any blood marks, bugs, or even the bites on her weren't the typical bedbug pattern, but what else could it be.

Then today it dawned on me, maybe she got the chickenpox! Well breakthrough chickenpox since she received the vaccine, but not the booster at her 4yr appt. I have 2 questions... is there a good way to tell the difference between the 2 easily because every picture I see online is extreme bedbugs or chicken pox and this would be a very mild case. Also I have a 2Mo old baby. Can she get them? I left a message with my dr office and am waiting for a return call but now I am super paranoid and scared for my little one!