Mastitis

So my LO is almost 3 months old. Last night I pumped for 15 minutes before going to bed. When I woke up at 3-4 this morning to feed him I noticed an achy feeling and cold chills all over my body. In the process of moving have lost my thermometer so I used my babies and it said 99.2. I feel super lethargic but I just don’t know what it could be after going to bed fine last night. I do work at his daycare so my two thoughts are either the flu or mastitis. My right boob is extremely tender and sore but Im not engorged and I have no lumps or hard places in my breasts either one... my left boob was a little larger but my LO just ate and it also went down. Is it possible to have mastitis without engorgement or blocked milk dukcs?