I would be more concerned, although we have enough talent and depth to get through the next few weeks. Based on reports, Salah, VVD, and Milner are fit, and Mane should be back soon enough, considering it is just his hand.
Lallana has been training for awhile now. Fabinho has started to get more minutes, and we have a favorable run of fixtures coming up. Hopefully Keita will back for Arsenal.