HELP ASAP IDK WHAT TO DO

My 4 month old daughter (19 weeks) has recently started crying A LOT.

She does gnaw on her hands and drool so I’m sure she’s teething however she will cry and cry and cry til like 1am then finally cry herself to sleep.

I have given her Tylenol Incase her teeth are hurting her, and I’ve given her gas drops. Nothing is helping. Me rocking her doesn’t help, she’s fed, changed, put her in a warm bath... I’m going crazy guys, I’m not frustrated with her however just frustrated that nothing I’m doing is helping her.

She hasn’t pooped since Friday, maybe she’s constipated?

Someone help. She’s just laying here screaming and has been for hours.

First time mom here, totally not sure what to do 😢😢😢