Yes it can take a lot longer than 3 weeks for it to show up on the refund site. The IRS is so backlogged it cannot keep up with original tax returns or amended returns. If you know that the return was received you will just have to be patient. Even in normal times it takes the IRS about 4 months to process an amended return; now it takes much longer.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**