Sometimes colostrum can appear quite thick and pink, so may not even be mastitis?
Sounds like she's well covered by the antibiotics if it is, if hard, hot udder, some anti-inflammatory painkillers may be of use, but if not, and the lambs are keen to suckle from her, i would leave them to it and keep an eye on them, like mentioned, making sure they stretch when you get them up, and don't look hunched up or hollow in the belly
best of luck with them
Suzanne