Yes, it does sound like a respiratory infection. Raising temperatures is a good idea but make sure to take to a reptile vet for evaluation
http://www.anapsid.org/rti.html
Symptoms and Diagnosis
Symptoms include listlessness, weight loss due to decreased appetite, swollen or bloated body, gaping, open mouth breathing, often with audible exhalations when in an advanced state. Wheezing may be heard, or clicking noises when breathing. Bubbly, stringy or sheeting mucous appears in the mouth. The head may be held in a raised position to facilitate breathing. In snakes, the tines of the forked tongue may be stuck together. Respiratory infections in snakes are especially dangerous in those snakes who have only one functioning lung (colubrids, etc.).
When you notice signs of a respiratory infection, not only must you evaluate and correct the environmental problems, but you must take the reptile to a reptile to be evaluated for systemic antibiotic therapy and possibly fluid and nutritional support. If the reptile does not respond to environmental correction and the antibiotic therapy, a culture and sensitivity should be done to determine exactly what the organism(s) is and the best antibiotic to combat it. The sample is easily taken by the vet in the form of a choanal swab or, in more difficult cases, a lung washing. In rare cases, the infection may be due to a fungal infection, which requires different medications than bacterial infections.
Treatment
Treating a respiratory infection requires two things: an immediate evaluation of the day and night temperatures in the reptile's enclosure, with additional heat sources added or broken/malfunctioning equipment replaced, and the attention of a reptile vet who will evaluate the reptile for systemic antibiotics and fluid replacement. In addition, if the reptile has cagemates or lives in a room where he is in line-of-site of other reptiles or household pets, an overall psychosocial evaluation needs to be made.
Reptile with respiratory infections should be kept in draft-free but well-ventilated enclosures maintained at the species' day time temperature gradient both during the day and at night. For reptiles who require a hotter basking area, the basking area temperatures do not need to be provided at night, but the higher overall gradient does. This will not only enable the reptile's own immune system to function better, but increases the efficacy of the antibiotics.