LED light therapy after IPL facial?

It is difficult to make a recommendation without knowing the depth of your treatment or the specifics of the device you use at home. You are likely correct that your home device is not terribly powerful, particularly if you perform that treatment multiple times a day. My guess is that it would be fine, but I encourage you to check with your provider just to be safe. 

LED can be done immediately after IPL.I would suggest a combination approach of :
1) skin care with products and PRP/microneedling
2) LED light therapy few times a month with growth factors
3) laser treatments like clear and brilliant regularly and a few times a year Fraxel, Viva, Co2/Erbium
4) Sculptra injections a few times a year for collagen production with fillers like juvederm/restylane/belotero/radiesse/bellafill
5) thermage/ultherapy for yearly skin tightening with or without PDO or cone based instalift threads for lifting
6) botox every 2-3 months to stop movement lines and prevent lines at rest
7) deep microneedling RF like Fractora/morpheus8 for tightening of the skin
Best, Dr. Emer.