On Effexor for five days can I just stop?

I was recently out on Effexor for anxiety and depression. My mom passed a few months ago and my anxiety has been so bad for most of my life, but manageable. Lately, it’s all consuming. So, I have been taking Effexor for five days and don’t like how I feel. I am Exhausted, my head is pounding, I am so thirsty and o have this weird jaw ache like I am clenching or something.

I have slept well, but I don’t think I can continue.

Should I give it longer or stop? Has anyone else been through this? I don’t know what to do.