Back home, she started crying in a high-pitched wail. So I buried myself in websites and forums to figure out why she was hurting.
Just a few hours later I'd convinced myself my daughter was dying. Comments and threads talked about vaccines causing lifelong issues and they told me I should never have let my daughter be jabbed with that needle.
Lydia realised she needed to vaccinate her kids to protect them. Photo / Supplied
It was all enough to terrify me to my core. I didn't realise it yet, but the community was preying on my normal parenthood anxieties.
And before bedtime that night, I was an anti-vaxxer.
At first I followed an alternate schedule skipping DTaP, and then I just stopped vaccinating my daughter completely.
I went on to have two more children, both of whom I refused to vaccinate.
My husband was on the fence about vaccinations but he didn't try to sway my opinion.
Anti-vaccination protesters hold a demonstration in Parliament Square, London yesterday. Photo / Getty Images
I stayed on the online forums and joined groups which convinced me I was right not to jab my kids. I believed in organic medicines and thought herd immunity through catching diseases and fighting them off was the way to go.
When my children were old enough for preschool, I also surrounded myself with anti-vax mums.
Looking back, it was frighteningly easy to build my own echo chamber around me. We all just convinced each other we were right. I knew people would judge me for my choices. So, I avoided any awkward conversations with friends or family.
Then 2020 happened. Headlines were flashing about a global pandemic called Covid-19.
In my small hometown in Canada, we started rationing food and toilet paper was flying off the shelves.
This is scary, I realised.
Almost instantly there was talk about the Covid-19 vaccine and the millions being poured into testing and research. It triggered me to rethink everything I thought I knew about vaccinations.
I took my first baby step out of the cultish anti-vax life by doing some evidence-based research. I started remembering how vaccine-preventable illnesses were coming back with a vengeance, like measles.
Bit by bit, every single trope I believed fell apart in front of my eyes. There was no link between vaccines and things like cancer or autism. My own beautiful son has autism – how could I have believed this?
Ultimately, I had to admit that I was wrong. About so many things. It took a lot of psychological discomfort to wipe away all my misconceptions about vaccinations.
And I needed to catch my three kids up on all their missed appointments.
So in April 2020, I watched as my daughter had her first vaccination in 12 years. At first, I worried I'd slap the needle out of the nurse's hand.
My two other kids were caught up on all their jabs, and I waited anxiously to see if they would have any side effects. Of course, they were all fine.
Just a few months earlier, I'd have fought tooth and nail to get a needle away from my child's precious arm. Now I was pro-vax!
This year, I was jabbed with the Moderna Covid-19 vaccination. I'm not afraid of it anymore. We needed to be protected against this awful, rapidly spreading disease.
I now know that vaccinations are safe and effective.
I've been a pro-vaxxer for a little over a year now and it's been a strange, surreal journey. I have even started nursing school so I can graduate to become a public health nurse, helping other parents with anxiety about vaccinations.
I think it takes a lot of strength to admit you are wrong – and I've done it many times since 2020.
It is hard to ignore 12 years of fear and misinformation.
That's why I started the Back to the Vax movement with fellow former anti-vaxxer Heather Simpson.
It is a safe space online for people who want to talk about changing their opinion.
