Hello. Welcome to hcm.
As the needle was injected thrice to get a venous line,it is possible that the vein was punctured on both ends and also caused muscle injury
. This causes blood to go out causing bruising. But presence of clots is very unusual after blood donation
. It can be that the vein is blocked and blood might have accumulated in vein.
I advice you to immedietly visit ER and get doppler ultrasound
done on hand to see for patency of vessels. Also apply cold
packs over lumps. Bruising will go soon with in a week or two as blood will be absorbed by the body.
All the best