Has anyone had to do innohep injections (blood thinners) from 28 weeks?

Just back from hospital due to reduce movements (been sick with flu and didn’t feel baby move as much for the last few hours but he started moving soon as the put the machine on 🤦‍♀️ and just a few soft moves here and there but scan also showed everything was good heartbeat and blood flow all good)

I am 28+6 today

I was told at 12 weeks I would need to take blood thinner injections from 28 weeks but when I asked at my appointment last week they said no need to take them) now I have been told I have to take them due to risk factors high bmi and taking clomid . I am also been on aspirin since 13 weeks.