Hi I got my cat Felix neurtered and first booster done on the 23rd of march.(well they done the second one first cuz they said it would be easier on him)Well on sat April 9th i noticed a lump on his left side right in the middle .Its about the size of a quarter and it hard.Its not bothering him in any way.So i called the vet and explained and they told me that it might be from his booster shot.The booster might not of dissolved and formed a lump but it will dissolve on its own.Well the lump is still there not getting a bigger or smaller.I have to bring Felix back for his next booster on tuesday so i will get checked then.Just wondering if anyone might know anything!!