If u have been feeling unwell and tired it can make a bit of sense that u may withdraw. Also i u r keeping a secret u may find it harder ti interact with friends etc. If things dont pick up in the second trimester, go and have a serious chat with your gp.
I'm guessing it's all the hormonal changes...they can really throw you off. Try not to think it's the new normal and instead that you will get back to yourself soon. Hopefully that will give you some hope.