Duplicate Certificate limit of 5 certificates per week

No, 7 days after the first.

Output of https://check-your-website.server-daten.de/?q=ifitfitsonline.com

CRT-Id Issuer not before not after Domain names LE-Duplicate next LE
1382902718 CN=Let's Encrypt Authority X3, O=Let's Encrypt, C=US 2019-04-13 18:37:58 2019-07-12 18:37:58 ifitfitsonline.com, www.ifitfitsonline.com duplicate nr. 5 next Letsencrypt certificate: 2019-04-15 21:41:51
1382561623 CN=Let's Encrypt Authority X3, O=Let's Encrypt, C=US 2019-04-13 14:54:11 2019-07-12 14:54:11 ifitfitsonline.com, www.ifitfitsonline.com duplicate nr. 4
1373879100 CN=Let's Encrypt Authority X3, O=Let's Encrypt, C=US 2019-04-09 11:34:19 2019-07-08 11:34:19 ifitfitsonline.com, www.ifitfitsonline.com duplicate nr. 3
1372231196 CN=Let's Encrypt Authority X3, O=Let's Encrypt, C=US 2019-04-08 23:04:37 2019-07-07 23:04:37 ifitfitsonline.com, www.ifitfitsonline.com duplicate nr. 2
1372230972 CN=CloudFlare Inc ECC CA-2, O="CloudFlare, Inc.", L=San Francisco, C=US, ST=CA 2019-04-08 22:00:00 2020-04-09 10:00:00 *.ifitfitsonline.com, CloudFlare, Inc., ifitfitsonline.com, sni.cloudflaressl.com
1372353905 CN=Let's Encrypt Authority X3, O=Let's Encrypt, C=US 2019-04-08 21:41:51 2019-07-07 21:41:51 ifitfitsonline.com, www.ifitfitsonline.com duplicate nr. 1

2019-04-15 you can create the next certificate.