I'm 4 w pregnant . is it wrong to sit in the pathtup with warm water and shower gel in it ?

No: It is okay to take a bath in pregnancy. However, there are two concerns: 1. Temperature-- it is easy to overheat when you are pregnant. When you do your core temperature can rise, which isn't good for the baby. Your blood pressure lowers and you feel light-headed. Therefore, try lukewarm baths and if you feel sweaty, lightheaded its too hot. 2. Infection-- this is a low risk in a clean tub.