16 week old not doing tummy time

My 3 & a half month old refuses to do tummy time on the boppy. a rolled up blanket a little biloppy... nothing I tried to put her arms under her to support herself but she just pulled her arms back and maybe does a minute her head is really strong when I'm lifting her walking around and she tries to sit up by herself I'm just really concerned that this isn't normal or a cat Let Her Cry like that for more than a minute because she's hysterical. Anybody else have this problem she's going to be 4 months on August 8th.