Lovenox question

Alison, 🌈 👶🏻 born 7/26/19

Im a little over 5 weeks pregnant and have been giving myself Lovenox injections due to a blood clotting disorder that caused me two miscarriages previously. So since I’ve been doing them for a few weeks the medicine itself stings... well this morning I did it and it didn’t sting. I notice sometimes it’s worse then others. Anyone have this experience? Just makes me wonder if I didn’t do it right this morning. Also, do you use an ice pack? I generally ice it for like a minute or two to make the area number before the shot but not afterwards. Thanks for your help!!