Another road block

I knew things were going too smoothly. Xavier has so far managed to have no ill effects from the radiation and has been developing by leaps and bounds for the past couple weeks. But today, the good news turned ugly.
We were told today Xavier has a blood clot where his new pic line was put in just two weeks ago. He was put on blood thinners which requires me to give him needles in his leg twice daily!
We had no idea there was a problem until yesterday when I noticed his left arm was a different colour than his right. He had a sock holding his pic line in place so I removed the sock thinking maybe it was too tight and cutting of his circulation. I waited a couple hours and his arm was still purplish. There was also a little bit of blood where his pic line entered his arm. By bedtime his arm was slightly swollen and still discoloured. We called the doc who said to keep measuring his arm to see if continues swelling. It was ok when we measured two hours later, so we left it for the night.
Today we went to 3F clinic to have the doctor have a look at it. He was immediately sent for an ultrasound where the clot was found. The tech couldn't tell us there, but we knew something was wrong when she told us to go back to the waiting room she was calling the doctor.
He had to get blood taken twice - one from the tiny vein in his hand and more from the vein in his foot. After all that, I had to give him his first shot of blood thinner. I hate the thought of having to prick my little boy, but I know it is for the best. I just hope he doesn't associate that with me and not like his mommy anymore.
And then poor Mackenzie. We had to ship her off to nearby relatives so we could be with Xavier at the hospital again. She looked so sad when we dropped her off. Those puppy dog eyes were ready to burst with tears. But our tough little girl held it in and had a great day.
Well it has been a long, stressful day (but what day isn't) and the kids are in bed now, so I am going to relax and take in, yet again, the bad news.