When you say HIIT 45 min, you mean HIIT cardio not weight training right ?
The Idea of HIIT is to get it down fast. HIIT is best done at Intensity Levels where you can keep it up for 16 min- 20...then the energy level if conntinued would decline dramatically..in fact IMO you should not be able to stay at HIIT for 45 min.
I think you need to change things from week to week. The body adjusts to stress...so try to change the structure of your training...type of cardio, intensity and type. Go off HIIT for a week...then start a new cycle
just an example:
cardio varied machines, intensity:
2 - 30 min sessions, 1 - 35 min session, 1 60 min session and one HIIT at 16 min, then add a second HIIT of 20 min ...
also when I am getting ready for a show and weight loss stalls I will do an evening cardio session, no food go to bed and next morn get up and do another session. This will kick you into gear (not sustainable for extended periods of time, emergency technique) ..also on occassion do cardio, weights, cardio...
weights try 3 on 1 off for 2 weeks, then 3 on 2 off then a few weeks later 4 on 2 off...and so one...
keep us updated on your progress...
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